Search: id:A104144
Results 1-1 of 1 results found.

%I A104144
%S A104144 0,0,0,0,0,0,0,0,1,1,2,4,8,16,32,64,128,256,511,1021,2040,4076,8144,16272,
               32512,64960,
%T A104144 129792,259328,518145,1035269,2068498,4132920,8257696,16499120,32965728,
%U A104144 65866496,131603200,262947072,525375999,1049716729,2097364960
%N A104144 a(n) = a(n-1)+a(n-2)+a(n-3)+a(n-4)+a(n-5)+a(n-6)+a(n-7)+a(n-8)+a(n-9).
%C A104144 Fibonacci 9-step numbers.
%C A104144 For n >= 8, this gives the number of integers written without 0 in base 
               ten, the sum of digits of which is equal to n-7. E.g. a(11)=8 because 
               we have the 8 numbers : 4, 13, 22, 31, 112, 121, 211, 1111.
%C A104144 The offset for this sequence is fairly arbitrary. - N. J. A. Sloane (njas(AT)research.att.com).
%H A104144 T. D. Noe, <a href="b104144.txt">Table of n, a(n) for n=0..208</a>
%H A104144 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               Fibonaccin-StepNumber.html">Fibonacci n-Step Number</a>
%F A104144 a(n)=sum_{k=1..9} a(n-k) for n>8, a(8)=1, a(n)=0 for n=0..7
%F A104144 a(1-10)=1,1,2,4,8,16,32,64,128,256. a(11 & following)=127*2^(n-9)+(.5+sqrt1.25)^(n-7)/
               sqrt5-(.5-sqrt1.25)^(n-7)/sqrt5. Offset 11. a(11)=511. [From Al Hakanson 
               (hawkuu(AT)gmail.com), Feb 14 2009]
%t A104144 a={1, 0, 0, 0, 0, 0, 0, 0, 0}; Table[s=Plus@@a; a=RotateLeft[a]; a[[ 
               -1]]=s, {n, 50}]
%Y A104144 Cf. A000045, A000073, A000078, A001591, A001592, A066178, A079262 (Fibonacci 
               n-step numbers).
%Y A104144 Sequence in context: A054046 A008861 A145115 this_sequence A123464 A113019 
               A069877
%Y A104144 Adjacent sequences: A104141 A104142 A104143 this_sequence A104145 A104146 
               A104147
%K A104144 nonn
%O A104144 0,11
%A A104144 Jean Lefort (jlefort.apmep(AT)wanadoo.fr), Mar 07 2005
%E A104144 Edited by N. J. A. Sloane (njas(AT)research.att.com), Aug 15 2006 and 
               again Nov 11 2006

Search completed in 0.001 seconds