login
A238547
Number of partitions p of n such that (number of parts of p) - min(p) is a part of p.
1
0, 1, 1, 2, 2, 3, 3, 6, 6, 10, 13, 18, 22, 33, 38, 52, 65, 85, 102, 135, 161, 208, 252, 316, 381, 481, 574, 711, 855, 1049, 1252, 1532, 1820, 2207, 2624, 3156, 3740, 4486, 5291, 6308, 7436, 8824, 10363, 12258, 14356, 16912, 19774, 23202, 27056, 31671, 36833
OFFSET
1,4
FORMULA
a(n) + A238548(n) = A000041(n).
EXAMPLE
a(6) counts these partitions: 71, 521, 41111.
MATHEMATICA
Table[Count[IntegerPartitions[n], p_ /; MemberQ[p, Length[p]-Min[p]]], {n, 50}]
PROG
(PARI) a(n) = {my(nb = 0); forpart(p=n, if (vecsearch(Vec(p), #p-vecmin(p)), nb++); ); nb; } \\ Michel Marcus, Jun 18 2015
CROSSREFS
Cf. A238548.
Sequence in context: A240579 A292225 A238786 * A325681 A116450 A054172
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Feb 28 2014
STATUS
approved