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%I #6 Jun 29 2021 09:06:15
%S 1,3,5,10,9,26,13,36,33,64,21,100,25,118,113,136,33,222,37,248,201,
%T 274,45,392,145,376,261,460,57,668,61,528,449,628,409,876,73,778,609,
%U 976,81,1272,85,1076,969,1126,93,1552,385,1520,1001,1480,105,1962,865,1816,1233,1768
%N a(n) = n + (n - 1) * (n - phi(n)).
%C For 1 <= k <= n, add 1 if gcd(n,k) = 1, otherwise add n. For n = 9, there are 6 numbers less than or equal to 9 that are relatively prime to 9 and 3 that are not. Then a(9) = 6*1 + 9*3 = 33.
%F a(n) = Sum_{k=1..n} n^(1 - floor(1/gcd(n,k))).
%t Table[n + (n - 1)*(n - EulerPhi[n]), {n, 50}]
%Y Cf. A000010 (phi), A051953 (cototient), A345891.
%K nonn
%O 1,2
%A _Wesley Ivan Hurt_, Jun 28 2021
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