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A101911 Binomial transform of A101910, where A101910(n) = a(A000120(n-1)) for n>0 with A101910(0) = 1. +0
2
1, 2, 5, 12, 30, 73, 169, 377, 831, 1842, 4110, 9136, 20006, 42906, 90148, 186414, 381955, 780966, 1603330, 3319952, 6949554, 14704880, 31379910, 67272276, 144212735, 307752571, 651353609, 1363714711, 2820488954, 5761343912 (list; graph; listen)
OFFSET

0,2

COMMENT

Also gives the records in A101910 at positions 2^n for n>=0. A000120 is the binary 1's-counting sequence.

FORMULA

a(n) = 1 + Sum_{k=0, n-1} C(n, k)*a(A000120(n-k-1)) for n>0, a(0)=1. a(n) = A101910(2^n) for n>=0.

EXAMPLE

Equals the binomial transform of A101910, where

A101910 = {1,1,2,2,5,2,5,5,12,2,5,5,12,5,12,12,30,...}

which has the following construction:

{1,a(0),a(1),a(1),a(2),a(1),a(2),a(2),a(3),...,a(A000120(n-1)),...}

where A000120 = {0,1,1,2,1,2,2,3,1,2,2,3,2,3,3,4,...}.

PROGRAM

(PARI) {a(n)=if(n==0, 1, 1+sum(k=0, n-1, binomial(n, k)*a(subst(Pol(binary(n-k-1)), x, 1))))}

CROSSREFS

Cf. A101910, A000120.

Sequence in context: A132807 A101411 A042789 this_sequence A052109 A046170 A062423

Adjacent sequences: A101908 A101909 A101910 this_sequence A101912 A101913 A101914

KEYWORD

eigen,nonn

AUTHOR

Paul D. Hanna (pauldhanna(AT)juno.com), Dec 21 2004

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Last modified November 30 22:12 EST 2008. Contains 150989 sequences.


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