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A238487
Number of partitions p of n not containing round((min(p) + max(p))/2) as a part.
1
0, 0, 0, 1, 2, 4, 6, 11, 14, 24, 30, 44, 57, 84, 102, 145, 180, 241, 302, 403, 494, 648, 796, 1015, 1253, 1593, 1941, 2439, 2969, 3680, 4477, 5523, 6672, 8176, 9847, 11968, 14385, 17406, 20816, 25066, 29896, 35802, 42587, 50819, 60214, 71585, 84594, 100151
OFFSET
1,5
COMMENTS
As used here, if k is a positive integer, then round(k + 1/2) = k + 1.
FORMULA
a(n) + A238486(n) = A000041(n).
EXAMPLE
a(6) counts these partitions: 51, 42, 411, 3111.
MATHEMATICA
Table[Count[IntegerPartitions[n], p_ /; !MemberQ[p, Round[(Min[p] + Max[p])/2]]], {n, 30}]
CROSSREFS
Cf. A238486.
Sequence in context: A274261 A156913 A238483 * A138461 A173397 A187492
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Feb 27 2014
STATUS
approved