Search: id:A022560 Results 1-1 of 1 results found. %I A022560 %S A022560 0,1,4,8,16,25,36,48,68,89,112,136,164,193,224,256,304,353,404,456,512, %T A022560 569,628,688,756,825,896,968,1044,1121,1200,1280,1392,1505,1620,1736, %U A022560 1856,1977,2100,2224,2356,2489,2624,2760,2900,3041 %N A022560 a(0)=0, a(2n) = 2a(n)+2a(n-1)+n^2+n, a(2n+1) = 4a(n)+(n+1)^2. %H A022560 R. Stephan, Some divide-and-conquer sequences ... %H A022560 R. Stephan, Table of generating functions %F A022560 Let a(i, n)=2^{i-1}\lfloor {1\over2}+{n\over 2^i}\rfloor; sequence is a_n=sum_{i=1}a(i, n)(n-a(i, n)). %F A022560 Second differences give A006519. Also a_1=0 and a_n=\lfloor n^2/4\rfloor + a_{\lfloor n/2\rfloor}+a_{\lceil n/2\rceil}. %F A022560 G.f.: 1/(1-x)^2 * (x/(1-x) + Sum(k>=1, 2^(k-1)*x^2^k/(1-x^2^k))). - Ralf Stephan (ralf(AT)ark.in-berlin.de), Apr 17 2003 %F A022560 a(0)=0, a(2n) = 2a(n)+2a(n-1)+n^2+n, a(2n+1) = 4a(n)+(n+1)^2. - Ralf Stephan (ralf(AT)ark.in-berlin.de), Sep 13 2003 %Y A022560 First differences are in A006520. %Y A022560 Cf. A070263. %Y A022560 Sequence in context: A137932 A140466 A161226 this_sequence A003451 A013934 A167189 %Y A022560 Adjacent sequences: A022557 A022558 A022559 this_sequence A022561 A022562 A022563 %K A022560 nonn %O A022560 0,3 %A A022560 Andre Kundgen (kundgen(AT)math.uiuc.edu) %E A022560 More terms from Ralf Stephan (ralf(AT)ark.in-berlin.de), Sep 13 2003 Search completed in 0.001 seconds