Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #13 Sep 24 2016 04:28:43
%S 1,4,11,16,15,12,23,44,45,40,41,72,93,98,99,48,133,108,109,160,117,
%T 172,81,120,217,176,159,102,221,144,187,262,169,304,375,276,241,158,
%U 211,316,273,72,313,320,397,406,227,582,335,236,187,460,293,274,663,178,433,538
%N Digital sum (base the n-th prime) of n^5.
%H G. C. Greubel, <a href="/A135105/b135105.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = ds_prime(n)(n^5), where ds_prime(n) = digital sum base the n-th prime.
%F a(n) = n^5 - (prime(n)-1)*Sum_{k>0} ( floor(n^5/prime(n)^k) ).
%e a(2) = ds_prime(2)(2^5) = ds_3(32) = 1+0+1+2 = 4;
%e a(6) = ds_prime(5)(5^5) = ds_11(3125) = 2+9+3+1 = 15.
%t Table[Total[IntegerDigits[n^5,Prime[n]]],{n,60}] (* _Harvey P. Dale_, Jul 19 2013 *)
%o (PARI) a(n) = vecsum(digits(n^5, prime(n))); \\ _Michel Marcus_, Sep 24 2016
%Y Cf. A000040, A007953, A054899, A075771, A131451, A133620, A133900, A134599.
%K nonn,base
%O 1,2
%A _Hieronymus Fischer_, Dec 24 2007