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%I #9 Dec 03 2014 23:14:52
%S 2,4,6,10,12,16,18,22,28,30,36,40,42,46,50,52,56,58,60,66,70,72,76,78,
%T 82,86,88,90,96,100,102,106,110,112,116,118,122,128,130,136,140,142,
%U 146,148,150,156,160,166,170,172,178,180,182,186,190,192,196,198,200,202
%N Degree of the special subgraph of Cayley graph constructed using the special (123)-avoiding and (132)-avoiding permutation patterns as generators.
%C This sequence is constructed using a special veriety of subgraphs of Cayley graphs in order for a study of the degree/diameter problem.
%D Ibrahim A.A. and Audu M.S.(2005) Some Group Theoretic Properties of Certain Class of (123) and (132)-Avoiding Patterns of Numbers: An Enumeration Scheme: An enumeration Scheme, African Journal of Natural Sciences, Vol. 8:79-84
%D Ibrahim A.A. (2006) A Counting Scheme And Some Algebraic Properties of A Class of Special Permutation Patterns. (in preparation)
%D Ibrahim A.A. (2005) On the Combinatorics of Succession In A 5-element Sample Abacus Journal of Mathematical Association of Nigeria Vol. 32, No. 2B:410-415
%F Recursion relation:f(0)=2, f(2)=4, f(3)=6, f(4)=12, f(5)=f(1)+f(2)+f(3)+f(4)/f(0), f(n)=f(n-1)+f(n-2)+f(n-3)+f(n-4)-f(n-5)/f(0)-f(n-5), n>5 and provided the difference between consecutive numbers (before and at the start of the addition) does not exceed four digits. If however, this difference (m-(m-1)<=4 the f(n)=f(n-1)+f(n-2)+f(n-3)+f(n-4)/f(0)-f(n-4). [Indices need to be changed to match the offset. - _R. J. Mathar_, Dec 04 2011]
%Y Cf. A123642, A128929.
%K nonn,uned
%O 3,1
%A _Aminu Alhaji Ibrahim_, Apr 30 2007
%E An obviously incorrect prime formula deleted. - _R. J. Mathar_, Dec 04 2011