id:A121688 - OEIS Search Results

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G.f.: A(x) = Sum_{k>=0} x^k * (1+x)^(2^k).

+0
2

1, 2, 3, 6, 15, 49, 210, 1191, 8981, 90405, 1219297, 22105506, 540476679, 17875316557, 802011318369, 48947781204529, 4073596070782653, 463360670014324153, 72183972733773232361, 15430254274957714069057 (list; graph; listen)

	OFFSET	`0,2`
	FORMULA	`a(n) = Sum_{k=0..n} C(2^k,n-k).`
	PROGRAM	`(PARI) a(n)=sum(k=0, n, binomial(2^k, n-k))`
	CROSSREFS	`Sequence in context: A110181 A141351 A088793 this_sequence A082094 A060796 A061059` `Adjacent sequences: A121685 A121686 A121687 this_sequence A121689 A121690 A121691`
	KEYWORD	`nonn`
	AUTHOR	`Paul D. Hanna (pauldhanna(AT)juno.com), Aug 15 2006`

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Last modified December 17 23:40 EST 2009. Contains 171025 sequences.

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