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A117087 Number of partitions of n such that the largest part and the smallest part are relatively prime. 0
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 (list; graph; refs; listen; history; text; internal format)
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: A075426 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

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Last modified October 19 03:34 EDT 2019. Contains 328211 sequences. (Running on oeis4.)