Algebraic Proof To A Problem Posted In Challenge 2
by
Huen Y.K.
CAHRC, P.O.Box 1003, Singapore 911101
http://web.singnet.com.sg/~huens/
email: huens@mbox3.singnet.com.sg
(A short communication - 1st released 3/11/97,revised 1/97 )
Abstract
Statement of Sequence Algebraic Challenge 2: Let Odd(z) represents the
contiguous odd integer set of {3,5,7,9,11,.... to any upperbound}. If the second largest odd
integer or the second smallest integer is removed from Odd(z) and squared, i.e. Odd(z)^2,
the resultant sequence of even integers will never be contiguous. Give an algebraic proof of
the above problem instead of an intuitive geometrical proof. Background information can be
obtained from:
(1) Some interesing contiguity properties
concerning Odd(z)^2.
(2) What is so special about GS1(109):0?
1. Introduction
This problem was originally posted as a challenge in this website on 1.9.97 and closed on
31.10.97. No correct solutions have been received. An algebraic proof based on order
analysis is presented by the author in this short paper. This is proved as a theorem.
Theorem 1: If the second largest odd or second smallest odd term from Odd(z) is
removed before squaring this sequence, the resultant even sequence will never be
contiguous.
Loss of contiguity needs only be the loss of one term in the original sequence. This proof is
made possible because we confine to the extremities of the sequence. In this proof, we only
consider the upper end. The same method can be used for the lower end. For convenience,
we take arbitrarily a sample of five consecutive odd terms in the upper end of Odd(z).
Proof: Take a general expression of the last five terms in Odd(z) as shown in equation (1).
.............................a(2 k - 7)....a(2 k - 5)....a(2 k - 3).....a(2 k - 1).....a(2 k + 1)
..............Odd(z) := ---------- + ---------- + ---------- + ---------- + ---------- ...............(1).
................................(2 k - 7).....(2 k - 5).....(2 k - 3)......(2 k - 1)......(2 k + 1)
...............................z................z.................z.................z..................z
Then squaring Odd(z) we get equation (2):
...................14..............2......12....................................10
..................z...a(2 k - 7).......z...a(2 k - 7) a(2 k - 5).....z....a(2 k - 7).a(2 k - 3)
Oddsq(z) := ----------- + 2 -----------------------+ 2 -------------------------
...........................k 4............................k 4................................k 4
......................(z )............................(z )................................(z )
..............10..............2......8.....................................8
............z....a(2 k - 5)......z..a(2 k - 7) a(2 k - 1).....z..a(2 k - 5).a(2 k - 3)
........+ --------------+ 2 ---------------------- + 2 ------------------------
......................k 4..........................k 4..............................k 4
.................(z )..........................(z )..............................(z )
................6.....................................6..................................6..............2
..............z a(2 k - 7) a(2 k + 1)......z a(2 k - 5) a(2 k - 1)...z a(2 k - 3)
........+ 2 ---------------------- + 2 --------------------- + --------------
.............................k 4.................................k 4..........................k 4
........................(z ).................................(z )..........................(z )
................4.....................................4...................................2
..............z a(2 k - 5) a(2 k + 1)......z..a(2 k - 3) a(2 k - 1)....z..a(2 k - 3) a(2 k + 1)
........+ 2 ----------------------+ 2 ----------------------+ 2 ------------------------
.............................k 4..................................k 4.................................k 4
........................(z )..................................(z ).................................(z )
..............2..............2.....................................................2
............z a(2 k - 1)......a(2 k - 1) a(2 k + 1)...a(2 k + 1)
..........+ ----------- + 2 --------------------+ ----------- .........................................(2).
.......................k 4.......................k 4................2.....k 4
..................(z ).......................(z )...................z..(z )
It will be noted from the second largest term (in bold fonts) in equation (2) that the numerator
expression is
given by the product of a(2*k-1) and a(2*k+1). In other words, the second largest term
depends only on the product of the numerators associated with the last and second last term
of Odd(z). Therefore if array a(2*k-1) is equated to zero, this term will be reduced to zero
thus
breaking contiguity. There cannot be further breaks in contiguities further down the sequence
since this is Odd(z) but for Prime(z) there could be additional breaks. This is an
algebraic proof since no specific values are
assigned to k. Furthermore, it is impossible for lower terms other than the second last and last term
to contribute to the numerator of the second last term. Q.E.D.
3. Conclusions
Sequence and order are important number theoretic properties which do not seem
to receive much attention from conventional number theory. Theorem 1 could be used to
explain qualitatively why there are so few full Goldbach sequences. In fact, beyond
GS1(109):0
no further full GS has been found up to the range of 1000,000,000. Although this
was not a very large search range, the present theorem hints at the rarity of full GS's
in the large integer end. The increasing gaps between primes do not favour the
formatons of full GS's.
4. References
(Comments: Not all papers are directly relevent but are included for the
benefit of readers who are new to sequence algebra.)
1. A Simple Introduction To Sequence
Algebra - by Huen Y.K.
(date release: 15.3.97) (38 KBytes, 11*A4 pages).
========================================================
2. The Canonical Generating Function
or CGF(z) ... - by Huen Y.K.
(date released : 27.5..97) (24 KBytes, 7*A4s).
========================================================
3. Final Value Theorem Applied To Number
Sequences... - by Huen Y.K. (date released : 5.6.97) (29.4 KBytes, 9*A4s).
========================================================
4. Unsolved Problems In Sequence
Algebra - by Huen Y.K. (date released : 6.6.97) (29.4 KBytes, 9*A4s).
========================================================
5. Lemmata, Corollaries, And
Theorems In Sequence Order Analysis. - by Huen Y.K. (date released : 6.7.97) (38.3
KBytes, 12*A4s).
========================================================
(6) The following articles are either published or in the press
but for copyright reasons, these cannot be reproduced here for download. Please contact
the publishers: Taylor & Francis Ltd., 1 Gunpowder Square, London, EC4A 3DE,
England,
for further information:
(i) Some interesting properties of the natural number
system, INT.J.MATH.EDUC.SCI.TECHNOL,
1996,VOL.27,NO.5,685-691.
(ii) Hgram patterns of Routh stability zones in linear
systems, INT.J.MATH.EDUC.SCI.TECHNOL,
1997,VOL.28,NO.2,225-241.
(iii) Visual algebra and its applications,
INT.J.MATH.EDUC.SCI.TECHNOL,
1997,VOL.28,NO.3, 333-344.
(iv) The twin prime problem revisited,
INT.J.MATH.EDUC.SCI.TECHNOL.,199?,VOL.??, NO.?,???-???, proof paper
mes-0488 (10 pages).
(v) Is Pie Periodic?,
INT.J.MATH.EDUC.SCI.TECHNOL.,199?,VOL.??,NO.?,???-???, (in the press).
========================================================
7. Some Interesting Contiguity
Properties Of Odd(z)^2 - by Huen Y.K. (date released : 15.8.97) (36.3 KBytes,
10*A4s).
========================================================
8. What Is So Special About
GS1(109):0 - by Huen Y.K. (date released : 16.8.97) (29.3 KBytes, 9*A4s).
======================== END OF PAPER ======================