A117087 Number of partitions of n such that the largest part and the smallest part are relatively prime.

1, 1, 2, 3, 6, 7, 14, 17, 26, 34, 53, 62, 94, 116, 157, 202, 275, 336, 452, 555, 719, 898, 1155, 1411, 1797, 2207, 2758, 3375, 4202, 5094, 6303, 7633, 9337, 11288, 13730, 16500, 19998, 23958, 28832, 34439, 41302, 49120, 58671, 69589, 82718, 97867, 115956

Offset

1,3

Links

Table of n, a(n) for n=1..47.

Maple

with(combinat): a:=proc(n) local P, ct, j: P:=partition(n): ct:=0: for j from 1 to numbpart(n) do if gcd(P[j][1], P[j][nops(P[j])])=1 then ct:=ct+1 else ct:=ct: fi: od: end: seq(a(n), n=1..50); # Emeric Deutsch, Apr 20 2006

Mathematica

Table[Count[IntegerPartitions[n], _?(GCD[First[#], Last[#]] == 1 &)], {n, 46}] (* Jayanta Basu, Jul 13 2013 *)

Crossrefs

Sequence in context: A359041 A191615 A018606 * A322367 A319811 A000837

Adjacent sequences: A117084 A117085 A117086 * A117088 A117089 A117090

Keyword

nonn

Author

Vladeta Jovovic, Apr 17 2006

Extensions

More terms from Emeric Deutsch, Apr 20 2006

Status

approved