Search: id:A001024 Results 1-1 of 1 results found. %I A001024 M4990 N2147 %S A001024 1,15,225,3375,50625,759375,11390625,170859375,2562890625,38443359375, %T A001024 576650390625,8649755859375,129746337890625,1946195068359375, %U A001024 29192926025390625,437893890380859375,6568408355712890625,98526125335693359375, 1477891880035400390625,22168378200531005859375,332525673007965087890625 %N A001024 Powers of 15. %C A001024 A000005(a(n)) = A000290(n+1). - Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Mar 04 2007 %C A001024 If X_1, X_2, ..., X_n is a partition of the set {1,2,...,2*n} into blocks of size 2 then, for n>=1, a(n) is equal to the number of functions f : {1,2,..., 2*n}->{1,2,3,4} such that for fixed y_1,y_2,...,y_n in {1,2,3,4} we have f(X_i)<>{y_i}, (i=1,2,...,n). - Milan R. Janjic (agnus(AT)blic.net), May 24 2007 %D A001024 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %D A001024 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence). %H A001024 T. D. Noe, Table of n, a(n) for n=0..100 %H A001024 P. J. Cameron, Sequences realized by oligomorphic permutation groups, J. Integ. Seqs. Vol. 3 (2000), #00.1.5. %H A001024 INRIA Algorithms Project, Encyclopedia of Combinatorial Structures 279 %H A001024 Milan Janjic, Enumerative Formulas for Some Functions on Finite Sets %H A001024 Tanya Khovanova, Recursive Sequences %H A001024 S. Plouffe, Approximations de S\'{e}ries G\'{e}n\'{e}ratrices et Quelques Conjectures, Dissertation, Universit\'{e} du Qu\'{e}bec \`{a} Montr\'{e}al, 1992. %H A001024 S. Plouffe, 1031 Generating Functions and Conjectures, Universit\'{e} du Qu\'{e}bec \`{a} Montr\'{e}al, 1992. %H A001024 Y. Puri and T. Ward, Arithmetic and growth of periodic orbits, J. Integer Seqs., Vol. 4 (2001), #01.2.1. %F A001024 G.f.: 1/(1-15x), e.g.f.: exp(15x) %p A001024 A001024:=-1/(-1+15*z); [S. Plouffe in his 1992 dissertation.] %o A001024 (Other) sage: [lucas_number1(n,15,0) for n in xrange(1, 18)]# [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Apr 29 2009] %Y A001024 a(n) = A159991(n)/A000302(n). [From Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), May 02 2009] %Y A001024 Sequence in context: A137916 A078364 A012852 this_sequence A012643 A067222 A154597 %Y A001024 Adjacent sequences: A001021 A001022 A001023 this_sequence A001025 A001026 A001027 %K A001024 nonn %O A001024 0,2 %A A001024 N. J. A. Sloane (njas(AT)research.att.com). %E A001024 More terms from James A. Sellers (sellersj(AT)math.psu.edu), Sep 19 2000 %E A001024 More terms from Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Aug 06 2009 Search completed in 0.001 seconds