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A117087
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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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0
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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
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OFFSET
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1,3
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LINKS
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MAPLE
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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
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MATHEMATICA
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Table[Count[IntegerPartitions[n], _?(GCD[First[#], Last[#]] == 1 &)], {n, 46}] (* Jayanta Basu, Jul 13 2013 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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