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%I #11 Apr 07 2022 10:56:05
%S 1,1,3,7,33,121,873,5167,45507,367927,4037913,39921961,522956313,
%T 6267300607,93445274187,1313941673647,22324392524313,355693695038761,
%U 6780385526348313,122000794104233527,2554923725074062867
%N Sum k!, where sum is over positive integers k <= n with gcd(k,n) = 1.
%e a(6) = 1! + 5! = 121 because 1 and 5 are the positive integers that are <= 6 and are relatively prime to 6.
%t Table[Total[Select[Range[n],CoprimeQ[#,n]&]!],{n,30}] (* _Harvey P. Dale_, Apr 07 2022 *)
%K nonn
%O 1,3
%A _Leroy Quet_, Nov 05 2000