A278780 Numbers n such that A000041(n) is of the form 2^3 * k for odd k.

11, 21, 75, 94, 98, 116, 120, 125, 128, 130, 133, 137, 141, 142, 180, 206, 231, 236, 243, 248, 255, 268, 292, 297, 303, 305, 322, 334, 340, 350, 364, 386, 397, 413, 415, 469, 471, 487, 494, 515, 550, 554, 605, 606, 609, 628, 631, 662, 676, 692, 699, 744, 745

Offset

1,1

Comments

Numbers n such that A278478(n) = 3.

Also numbers n such that A000041(n) has three times as many even divisors as odd divisors.

Links

Colin Barker, Table of n, a(n) for n = 1..1000

Formula

A000041(a(n)) = A278197(n).

Prog

(PARI) isok(n) = valuation(numbpart(n), 2)==3;
select(n->isok(n), vector(1000, n, n))

Crossrefs

Cf. A000041, A278197, A278779, A278781, A278782, A278783, A278784.

Positions of 3's in A278478.

Sequence in context: A146150 A244069 A058489 * A071158 A255765 A071157

Adjacent sequences: A278777 A278778 A278779 * A278781 A278782 A278783

Keyword

nonn

Author

Colin Barker, Nov 28 2016

Status

approved