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%I #11 Apr 29 2022 20:51:28
%S 0,2,13,4,15,26,37,25,41,36,45,47,62,67,57,67,60,92,19,76,116,99,23,
%T 105,63,120,124,134,133,110,140,155,141,130,132,168,137,103,184,176,
%U 182,226,188,217,168,145,186,220,245,170,221,228,232,267,216,225,179,259
%N Sum of all decimal digits of distinct prime factors for n-th repunit.
%H Max Alekseyev, <a href="/A095417/b095417.txt">Table of n, a(n) for n = 1..352</a> (first 322 terms from Giovanni Resta)
%F a(n) = A095402(A002275(n)).
%e n=60: concatenated distinct-prime factor-set for 60th-repunit is:
%e 371113313741611012112412712161354190919901279612906161418890139526741,
%e its digit sum=a(60)=244.
%t a[1]=0; a[n_] := Total[ Flatten[ IntegerDigits /@ First /@ FactorInteger[(10^n - 1)/9]]]; Array[a, 60] (* _Giovanni Resta_, Jul 19 2018 *)
%Y Cf. A095402, A002275, A095370, A095413-A095418.
%K base,nonn
%O 1,2
%A _Labos Elemer_, Jun 22 2004
%E Data corrected by _Giovanni Resta_, Jul 19 2018
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