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%I #22 Apr 29 2023 08:10:16
%S 0,2,4,6,8,1,3,5,7,9,2,4,6,8,10,3,5,7,9,11,4,6,8,10,12,5,7,9,11,13,6,
%T 8,10,12,14,7,9,11,13,15,8,10,12,14,16,9,11,13,15,17,1,3,5
%N Sum of digits of even numbers.
%C a(n) >= A007953(n) / 5 with equality iff n is in A169964 (see Diophante link). - _Bernard Schott_, Apr 29 2023
%H G. C. Greubel, <a href="/A004092/b004092.txt">Table of n, a(n) for n = 0..10000</a>
%H Diophante, <a href="http://www.diophante.fr/problemes-par-themes/arithmetique-et-algebre/a1-pot-pourri/5453-a1762-des-chiffres-a-la-moulinette">A1762, Des chiffres à la moulinette</a> (in French).
%F a(n) = 2n - 9*Sum_{k=1..1+floor(log_10(2n))} floor( n/(5*10^(k-1)) ). - _Anthony Browne_, Jun 18 2016
%F a(n) = A007953(2n). - _Alois P. Heinz_, Apr 11 2018
%t Table[Sum[DigitCount[2*n][[i]]*i, {i, 9}], {n, 0, 100}] (* _G. C. Greubel_, Jun 19 2016 *)
%o (PARI) a(n)=sumdigits(2*n) \\ _Charles R Greathouse IV_, Jun 19 2016
%Y Cf. A007953, A169964.
%K nonn,base,easy
%O 0,2
%A _N. J. A. Sloane_, Dec 11 1996
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