Search: id:A001018 Results 1-1 of 1 results found. %I A001018 M4555 N1937 %S A001018 1,8,64,512,4096,32768,262144,2097152,16777216,134217728,1073741824, %T A001018 8589934592,68719476736,549755813888,4398046511104,35184372088832,281474976710656, %U A001018 2251799813685248,18014398509481984,144115188075855872,1152921504606846976, 9223372036854775808,73786976294838206464,590295810358705651712 %N A001018 Powers of 8. %C A001018 Same as Pisot sequences E(1,8), L(1,8), P(1,8), T(1,8). See A008776 for definitions of Pisot sequences. %C A001018 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} such that for fixed y_1,y_2,...,y_n in {1,2,3} we have f(X_i)<>{y_i}, (i=1,2,...,n). - Milan R. Janjic (agnus(AT)blic.net), May 24 2007 %C A001018 With a different offset, number of n-permutations (n>=0) of 9 objects: r, s, t, u, v, w, z, x, y with repetition allowed, containing exactly zero (0) or free u's. - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jul 15 2008 %C A001018 1/1 + 1/8 + 1/64 + 1/512 + 1/4096 + ... = 8/7 [From Gary W. Adamson (qntmpkt(AT)yahoo.com), Aug 29 2008] %C A001018 a(n) = A157176(A008588(n)); a(n+1) = A157176(A016969(n)). [From Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Feb 24 2009] %C A001018 This is the auto-convolution (convolution square) of A059304. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), May 25 2009] %D A001018 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence). %D A001018 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %H A001018 T. D. Noe, Table of n, a(n) for n=0..100 %H A001018 P. J. Cameron, Sequences realized by oligomorphic permutation groups, J. Integ. Seqs. Vol. 3 (2000), #00.1.5. %H A001018 INRIA Algorithms Project, Encyclopedia of Combinatorial Structures 273 %H A001018 Milan Janjic, Enumerative Formulas for Some Functions on Finite Sets %H A001018 Tanya Khovanova, Recursive Sequences %H A001018 Y. Puri and T. Ward, Arithmetic and growth of periodic orbits, J. Integer Seqs., Vol. 4 (2001), #01.2.1. %H A001018 Eric Weisstein's World of Mathematics, Sierpinski Carpet %H A001018 Index entries for sequences related to linear recurrences with constant coefficients %F A001018 a(n) = 8^n; a(n) = 8a(n-1). %F A001018 G.f.: 1/(1-8x), e.g.f.: exp(8x) %p A001018 with(finance):seq(futurevalue(1,7,n), n=0..20);# [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Mar 25 2009] %o A001018 (Other) sage: [lucas_number1(n,8,0) for n in xrange(1, 22)]# [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Apr 23 2009] %Y A001018 A013730, A103333, A013731, A067417, A083233, A055274. [From Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Feb 24 2009] %Y A001018 Sequence in context: A126629 A125498 A125908 this_sequence A097682 A050738 A046238 %Y A001018 Adjacent sequences: A001015 A001016 A001017 this_sequence A001019 A001020 A001021 %K A001018 nonn,easy %O A001018 0,2 %A A001018 N. J. A. Sloane (njas(AT)research.att.com). %E A001018 More terms a(21), a(22), a(23) from Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Aug 06 2009 Search completed in 0.002 seconds