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A278781
Numbers m such that A000041(m) is of the form 2^4 * k for odd k.
7
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 m such that A278478(m) = 4.
Also numbers m such that A000041(m) has four times as many even divisors as odd divisors.
LINKS
FORMULA
A000041(a(n)) = A278198(n).
MATHEMATICA
Select[Range[1700], IntegerExponent[PartitionsP[#], 2] == 4 &] (* Amiram Eldar, May 25 2024 *)
PROG
(PARI) isok(n) = valuation(numbpart(n), 2)==4;
select(n->isok(n), vector(2000, n, n))
CROSSREFS
Positions of 4's in A278478.
Sequence in context: A143727 A231327 A041426 * A275644 A074877 A293263
KEYWORD
nonn
AUTHOR
Colin Barker, Nov 28 2016
STATUS
approved