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%I #25 Sep 08 2022 08:45:04
%S 1,7,13,10,7,22,28,25,31,28,43,49,37,52,58,64,52,58,73,79,76,82,97,85,
%T 73,97,112,91,133,121,118,115,103,127,142,157,136,115,130,136,142,148,
%U 136,169,175,163,187,175,136,178,184,217,196,220,217
%N Sum of digits of 7^n.
%H Harry J. Smith, <a href="/A066003/b066003.txt">Table of n, a(n) for n=0,...,1000</a>
%F a(n) = A007953(A000420(n)). - _Michel Marcus_, Nov 01 2013
%t Table[Total[IntegerDigits[7^n]],{n,55}] (* _Harvey P. Dale_, Nov 22 2010 *)
%o (Magma) [ &+Intseq(7^n): n in [0..60] ];
%o (PARI) a(n) = sumdigits(7^n); \\ _Michel Marcus_, Nov 01 2013
%Y Cf. A000420 (7^n), A007953 (sum of digits).
%Y Cf. sum of digits of k^n: A001370 (k=2), A004166 (k=3), A065713 (k=4), A066001 (k=5), A066002 (k=6), this sequence (k=7), A066004 (k=8), A065999 (k=9), A066005 (k=11), A066006 (k=12), A175527 (k=13).
%K nonn,base
%O 0,2
%A _N. J. A. Sloane_, Dec 11 2001