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%I #21 Jan 12 2025 10:17:33
%S 2,3,5,10,27,104,541,3498,26615,231172,2250129,24227486,285705643,
%T 3660694200,50624828357,751426146514,11913622408671,200919532718828,
%U 3591112295892985,67803855263483142,1348467602319393299,28174602435230023456,617001101156944493613,14131835969321147283770
%N Occurrences of 2's in A088936.
%F a(n) = 2 + (1/2)*Sum_{k=1..n-1} Sum_{i=0..k} i!. - _Benoit Cloitre_ and Claude Lenormand
%t a[n_] := 2 + Sum[i!, {k, 1, n-1}, {i, 0, k}]/2; Array[a, 30] (* _Amiram Eldar_, Jan 12 2025 *)
%Y Cf. A088936, A088937, A088939, A088940.
%K nonn
%O 1,1
%A _Benoit Cloitre_, Oct 25 2003