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A101693 A modular binomial sum transform of 2^n. 1
1, 1, 5, 1, 21, 1, 5, 17, 341, 1, 5, 17, 85, 257, 1285, 4369, 87381, 1, 5, 17, 85, 257, 1285, 4369, 21845, 65537, 327685, 1114129, 5570645, 16843009, 84215045, 286331153, 5726623061, 1, 5, 17, 85, 257, 1285, 4369, 21845, 65537, 327685, 1114129, 5570645 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

a(2^n)=A101694(n); b(2^n+1) is 5,1,1,1,....

LINKS

Table of n, a(n) for n=0..44.

FORMULA

a(n)=sum{k=0..n, mod(binomial(2n-2, k), 2)2^k}

MATHEMATICA

Table[Sum[Mod[Binomial[2n-2, k], 2]2^k, {k, 0, n}], {n, 0, 50}] (* Harvey P. Dale, Nov 23 2019 *)

CROSSREFS

Cf. A001045.

Sequence in context: A049411 A070729 A296306 * A063476 A126325 A278544

Adjacent sequences:  A101690 A101691 A101692 * A101694 A101695 A101696

KEYWORD

easy,nonn

AUTHOR

Paul Barry, Dec 11 2004

STATUS

approved

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Last modified September 21 20:10 EDT 2021. Contains 347598 sequences. (Running on oeis4.)