A278781 Numbers n such that A000041(n) is of the form 2^4 * k for odd k.

15, 106, 122, 131, 136, 253, 295, 327, 339, 383, 412, 449, 465, 517, 520, 551, 580, 581, 599, 602, 632, 648, 669, 677, 776, 806, 815, 838, 904, 927, 1071, 1137, 1166, 1174, 1199, 1263, 1275, 1298, 1325, 1375, 1399, 1404, 1425, 1554, 1564, 1641, 1684, 1688

Offset

1,1

Comments

Numbers n such that A278478(n) = 4.

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

Links

Colin Barker, Table of n, a(n) for n = 1..600

Formula

A000041(a(n)) = A278198(n).

Prog

(PARI) isok(n) = valuation(numbpart(n), 2)==4;
select(n->isok(n), vector(2000, n, n))

Crossrefs

Cf. A000041, A278198, A278779, A278780, A278782, A278783, A278784.

Positions of 4's in A278478.

Sequence in context: A143727 A231327 A041426 * A275644 A074877 A293263

Adjacent sequences: A278778 A278779 A278780 * A278782 A278783 A278784

Keyword

nonn

Author

Colin Barker, Nov 28 2016

Status

approved