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%I #29 Feb 21 2024 16:38:41
%S 0,1,3,13,11,127,427,13789,79939,550339,4360579,428990369,4270982369,
%T 608769618797,7287249426797,94552718917997,1321723383637997,
%U 336624987690165949,5380569124281525949,1736468713616949633031,31234462813230541185031,593101017091584665985031
%N a(n) is the numerator of Sum_{i=1..n} i!/(i^2).
%F Numerator of Sum_{i=1..n} A000142(i)/A000290(i).
%t Join[{0},Accumulate[Table[k!/k^2,{k,30}]]]//Numerator (* _Harvey P. Dale_, Feb 21 2024 *)
%o (PARI) a(n) = numerator(sum(i=1, n, i!/i^2)); \\ _Michel Marcus_, Mar 18 2018
%Y Cf. A121566 (denominator).
%K easy,frac,nonn
%O 0,3
%A _Jonathan Vos Post_, Aug 07 2006
%E a(0) corrected by _Michel Marcus_, Jun 13 2022
%E a(11) corrected by _Georg Fischer_, Jan 05 2024