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A320322
Number of integer partitions of n whose product is a perfect power.
34
1, 0, 0, 0, 2, 2, 5, 5, 9, 11, 18, 19, 28, 30, 42, 50, 68, 76, 102, 113, 146, 170, 212, 241, 312, 356, 441, 514, 628, 720, 887, 1008, 1215, 1403, 1660, 1903, 2291, 2609, 3107, 3594, 4254, 4864, 5739, 6546, 7672, 8811, 10237, 11651, 13583, 15420, 17867, 20382
OFFSET
0,5
EXAMPLE
The a(4) = 2 through a(11) = 19 integer partitions:
4 41 33 331 8 9 55 551
22 221 42 421 44 81 82 632
222 2221 422 333 91 821
411 4111 2222 441 433 911
2211 22111 3311 4221 442 4331
4211 22221 811 4421
22211 33111 3322 8111
41111 42111 3331 33221
221111 222111 4222 33311
411111 4411 42221
2211111 22222 44111
42211 222221
222211 422111
331111 2222111
421111 3311111
2221111 4211111
4111111 22211111
22111111 41111111
221111111
MATHEMATICA
Table[Length[Select[IntegerPartitions[n], GCD@@FactorInteger[Times@@#][[All, 2]]>1&]], {n, 30}]
KEYWORD
nonn
AUTHOR
Gus Wiseman, Oct 10 2018
STATUS
approved