id:A097139 - OEIS Search Results

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Convolution of 5^n and floor(n/2).

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0, 0, 1, 6, 32, 162, 813, 4068, 20344, 101724, 508625, 2543130, 12715656, 63578286, 317891437, 1589457192, 7947285968, 39736429848, 198682149249, 993410746254, 4967053731280, 24835268656410, 124176343282061, 620881716410316 (list; graph; listen)

	OFFSET	`0,4`
	COMMENT	`a(n+1) gives partial sums of A033115 and second partial sums of A015531.`
	FORMULA	`G.f. : x^2/((1-x)(1-5x)(1-x^2)); a(n)=sum{k=0..n, floor((n-k)/2)4^k}=sum{k=0..n, floor(k/2)4^(n-k)}; a(n)=6(n-1)-4a(n-2)-6a(n-3)+5a(n-4).`
	CROSSREFS	`Sequence in context: A006668 A037530 A083320 this_sequence A034942 A046714 A129171` `Adjacent sequences: A097136 A097137 A097138 this_sequence A097140 A097141 A097142`
	KEYWORD	`easy,nonn`
	AUTHOR	`Paul Barry (pbarry(AT)wit.ie), Jul 29 2004`

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Last modified November 29 12:46 EST 2009. Contains 167659 sequences.

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