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A161324 Let b(n,k) = the k-th binary digit (starting at k=1, reading right to left) in the base 2 representation of n. (So: n = sum{k>=0} b(k+1)*2^k.) A positive integer n is included in this sequence if and only if n = product{k>=1} k^b(n,k). 0
1, 2, 6, 12, 576000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Hans Havermann found term a(5).

Jack Brennen says that there are no other terms < 2^32.

a(6) > 2^80 if it exists. - Bert Dobbelaere, Apr 19 2019

LINKS

Table of n, a(n) for n=1..5.

EXAMPLE

12 in binary is 1100. And 12 = 4^1 * 3^1 * 2^0 * 1^0. So 12 is in the sequence.

CROSSREFS

Sequence in context: A089415 A282974 A181063 * A226603 A116534 A130533

Adjacent sequences:  A161321 A161322 A161323 * A161325 A161326 A161327

KEYWORD

base,more,nonn

AUTHOR

Leroy Quet, Jun 07 2009

STATUS

approved

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Last modified October 21 22:47 EDT 2019. Contains 328315 sequences. (Running on oeis4.)