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A295577
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a(1)=1; thereafter, a(n+1) = Sum_{d divides n} (n!/(d!*(n/d)!))*a(d).
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4
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1, 1, 2, 3, 10, 11, 192, 193, 3554, 23715, 190036, 190037, 20813718, 20813719, 1690001240, 23484574041, 182792522842, 182792522843, 50810028382044, 50810028382045, 18982767399108446, 346748732389572447, 3022335531740638048, 3022335531740638049, 1128891498261322308450, 11900565139463395908451
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OFFSET
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1,3
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COMMENTS
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It is possible that A092986 (Maia and Mendez, 2008, Table 1) is an erroneous version of this sequence.
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LINKS
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MAPLE
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with(numtheory);
f:=proc(n) local d; option remember;
if n=1 then 1
else add( ((n-1)!/(d!*((n-1)/d)!))*f(d), d in divisors(n-1)); fi;
end;
[seq(f(n), n=1..40)];
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MATHEMATICA
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f[n_] := Block[{m = n - 1}, Plus @@ Flatten[((m!/(#!*(m/#)!))*f@#) & /@ Divisors@ m]]; f[1] = 1; Array[f, 26] (* Robert G. Wilson v, Dec 10 2017 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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