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A071639 Numbers n such that core(n) = b(n,1)*b(n,0) where b(n,1) is the number of 1's in binary representation of n, b(n,0) the number of 0's and core(n) the squarefree part of n. 0
24, 3500, 6048, 52855, 56320, 67270, 71874, 80920, 85536, 95830, 105600, 112000, 117670, 131625, 142373, 155925, 250173, 262392, 280800, 350142, 360672 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..21.

PROG

(PARI) for(s=1, 500000, b=binary(s); l=length(b); if(sum(i=1, l, if(component(b, i)-1, 0, 1))*sum(i=1, l, if(component(b, i), 0, 1))==core(s), print1(s, ", ")))

CROSSREFS

Sequence in context: A072529 A159681 A275569 * A061530 A275637 A223123

Adjacent sequences:  A071636 A071637 A071638 * A071640 A071641 A071642

KEYWORD

easy,nonn

AUTHOR

Benoit Cloitre, Jun 22 2002

STATUS

approved

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Last modified August 20 23:38 EDT 2019. Contains 326155 sequences. (Running on oeis4.)