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A316432
Number of integer partitions of n whose length is equal to the GCD of all parts.
10
1, 0, 0, 1, 0, 1, 0, 1, 1, 2, 0, 2, 0, 3, 2, 3, 0, 5, 0, 3, 4, 5, 0, 8, 1, 6, 6, 6, 0, 11, 0, 8, 10, 8, 2, 18, 0, 9, 14, 15, 0, 19, 0, 16, 21, 11, 0, 34, 1, 16, 24, 24, 0, 30, 10, 27, 30, 14, 0, 71, 0, 15, 34, 38, 18, 47, 0, 47, 44, 36, 0, 88, 0, 18, 79, 63, 5
OFFSET
1,10
EXAMPLE
The a(24) = 8 partitions:
(14,10), (22,2),
(9,9,6), (12,9,3), (15,6,3), (18,3,3),
(8,8,4,4), (12,4,4,4).
MATHEMATICA
Table[Length[Select[IntegerPartitions[n], GCD@@#==Length[#]&]], {n, 30}]
PROG
(PARI) a(n) = {my(nb = 0); forpart(p=n, if (gcd(p)==#p, nb++); ); nb; } \\ Michel Marcus, Jul 03 2018
KEYWORD
nonn
AUTHOR
Gus Wiseman, Jul 02 2018
STATUS
approved