id:A117909 - OEIS Search Results

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1, 2, 0, 3, 4, 0, 5, 6, 0, 7, 8, 0, 9, 10, 0, 11, 12, 0, 13, 14, 0, 15, 16, 0, 17, 18, 0, 19, 20, 0, 21, 22, 0, 23, 24, 0, 25, 26, 0, 27, 28, 0, 29, 30, 0, 31, 32, 0, 33, 34, 0, 35, 36, 0, 37, 38, 0, 39, 40, 0, 41, 42, 0, 43, 44, 0, 45, 46, 0, 47, 48, 0, 49, 50, 0, 51, 52, 0, 53, 54, 0 (list; graph; listen)

	OFFSET	`0,2`
	COMMENT	`Row sums of A117908.`
	FORMULA	`G.f.: (1+2x+x^3)/(1-x^3)^2; a(n)=sum{k=0..n, 0^abs(L(C(n,2)/3)-2*L(C(k,2)/3))} where L(j/p) is the Legendre symbol of j and p.`
	CROSSREFS	`Cf. A009947.` `Sequence in context: A102389 A099091 A078436 this_sequence A091538 A013584 A137372` `Adjacent sequences: A117906 A117907 A117908 this_sequence A117910 A117911 A117912`
	KEYWORD	`easy,nonn`
	AUTHOR	`Paul Barry (pbarry(AT)wit.ie), Apr 01 2006`

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Last modified November 24 23:16 EST 2009. Contains 167481 sequences.

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