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Number of partitions of n such that the largest part and the smallest part are relatively prime.
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%I #10 Jul 23 2013 20:44:26

%S 1,1,2,3,6,7,14,17,26,34,53,62,94,116,157,202,275,336,452,555,719,898,

%T 1155,1411,1797,2207,2758,3375,4202,5094,6303,7633,9337,11288,13730,

%U 16500,19998,23958,28832,34439,41302,49120,58671,69589,82718,97867,115956

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

%p 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

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

%K nonn

%O 1,3

%A _Vladeta Jovovic_, Apr 17 2006

%E More terms from _Emeric Deutsch_, Apr 20 2006