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A136494 Number of permutation symmetries in the binary expansion of n. 1
1, 1, 1, 2, 2, 2, 2, 6, 6, 4, 4, 6, 4, 6, 6, 24, 24, 12, 12, 12, 12, 12, 12, 24, 12, 12, 12, 24, 12, 24, 24, 120, 120, 48, 48, 36, 48, 36, 36, 48, 48, 36, 36, 48, 36, 48, 48, 120, 48, 36, 36, 48, 36, 48, 48, 120, 36, 48, 48, 120, 48, 120, 120, 720, 720 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

LINKS

Andrew Howroyd, Table of n, a(n) for n = 0..1023

FORMULA

a(n) = A093659(n) * A139329(n).

a(n) = A000120(n)! * A080791(n)!.

EXAMPLE

a(14) = 6 because there are 3! permutation symmetries of 1's * the 0! permutation symmetries of 0's.

PROG

(PARI) a(n) = {if(n==0, 1, my(w=hammingweight(n)); w!*(1+logint(n, 2)-w)!)} \\ Andrew Howroyd, Jan 12 2020

CROSSREFS

Cf. A000120, A080791, A093659, A139329.

Sequence in context: A110023 A279466 A116863 * A260188 A048764 A327663

Adjacent sequences:  A136491 A136492 A136493 * A136495 A136496 A136497

KEYWORD

base,nonn

AUTHOR

Max Sills, Apr 13 2008

EXTENSIONS

Terms a(32) and beyond from Andrew Howroyd, Jan 12 2020

STATUS

approved

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Last modified October 18 17:15 EDT 2021. Contains 348068 sequences. (Running on oeis4.)