id:A000773 - OEIS Search Results

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Number of numbers == 0 (mod 3) in range 2^n to 2^n+1 with odd number of 1's in binary expansion.

+0
2

0, 0, 0, 1, 1, 6, 8, 29, 45, 130, 220, 561, 1001, 2366, 4368, 9829, 18565, 40410, 77540, 164921, 320001, 669526, 1309528, 2707629, 5326685, 10919090, 21572460, 43942081, 87087001, 176565486, 350739488 (list; graph; listen)

	OFFSET	`1,6`
	FORMULA	`a(n) = (1/6)*{2^n - (-1)^n - 3^[(n+1)/2]}. G.f.: x^3 / [(1+x)(1-2x)(1-3x^2)]. - Ralf Stephan, Aug 08 2004`
	CROSSREFS	`Cf. A000069.` `Sequence in context: A024873 A066231 A007829 this_sequence A039720 A056097 A099431` `Adjacent sequences: A000770 A000771 A000772 this_sequence A000774 A000775 A000776`
	KEYWORD	`easy,nonn`
	AUTHOR	`Russ Cox (rsc(AT)swtch.com)`

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Last modified November 25 20:09 EST 2009. Contains 167514 sequences.

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