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%I #13 Jul 09 2018 02:56:21
%S 0,2,5,11,16,30,37,149,221,369,380,1310,1323,2389,2975,33695,33712,
%T 72312,72331,269439,282855,545109,545132,4254514,4269514,8463974,
%U 9999248,35167130,35167159,71972737,71972768,2152347552,2161914700
%N a(n) = A008475(n!).
%e a(1) = 0 since 1! = 1 has no prime factor;
%e a(8) = 2^7 + 3^2 + 5 + 7 = 149 since 8! = 2^7*3^2*5*7.
%t ffi[x_] := Flatten[FactorInteger[x]] lf[x_] := Length[FactorInteger[x]] ba[x_] := Table[Part[ffi[x], 2*w-1], {w, 1, lf[x]}] ep[x_] := Table[Part[ffi[x], 2*w], {w, 1, lf[x]}] supo[x_] := Apply[Plus, ba[x]^ep[x]] Table[supo[w], {w, 1, 25}]
%o (PARI) a(n) = my(f=factor(n!)); sum(k=1, #f~, f[k,1]^f[k,2]); \\ _Michel Marcus_, Jul 09 2018
%Y Cf. A008475, A000142, A081403, A081404.
%K nonn
%O 1,2
%A _Labos Elemer_, Mar 31 2003
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