id:A097138 - OEIS Search Results

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Convolution of 4^n and floor(n/2).

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0, 0, 1, 5, 22, 90, 363, 1455, 5824, 23300, 93205, 372825, 1491306, 5965230, 23860927, 95443715, 381774868, 1527099480, 6108397929, 24433591725, 97734366910, 390937467650, 1563749870611, 6254999482455, 25019997929832 (list; graph; listen)

	OFFSET	`0,4`
	COMMENT	`a(n+1) gives partial sums of A033114 and second partial sums of A015521.`
	FORMULA	`G.f. : x^2/((1-x)(1-4x)(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)=5a(n-1)-3a(n-2)-5a(n-3)+4a(n-4).`
	CROSSREFS	`Sequence in context: A108072 A081892 A128566 this_sequence A050185 A085812 A053297` `Adjacent sequences: A097135 A097136 A097137 this_sequence A097139 A097140 A097141`
	KEYWORD	`easy,nonn`
	AUTHOR	`Paul Barry (pbarry(AT)wit.ie), Jul 29 2004`

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Last modified November 27 22:38 EST 2009. Contains 167602 sequences.

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