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Base 10 digit sum of 11*n.
1

%I #20 Aug 07 2014 04:47:20

%S 0,2,4,6,8,10,12,14,16,18,2,4,6,8,10,12,14,16,18,11,4,6,8,10,12,14,16,

%T 18,11,13,6,8,10,12,14,16,18,11,13,15,8,10,12,14,16,18,11,13,15,17,10,

%U 12,14,16,18,11,13,15,17,19,12,14,16,18,11,13,15,17,19,21,14,16,18,11,13,15,17,19,21,23,16,18,11,13,15,17,19,21,23,25,18,2

%N Base 10 digit sum of 11*n.

%C First term that differs from A136614 is a(91) = 2, compared to A136614(91) = 11.

%H Robert Israel, <a href="/A245627/b245627.txt">Table of n, a(n) for n = 0..10000</a>

%F a(n) = A007953(A008593(n)). - _Tom Edgar_, Jul 27 2014

%e a(90) = 18 because 11 * 90 = 990 and 9 + 9 + 0 = 18.

%e a(91) = 2 because 11 * 91 = 1001 and 1 + 0 + 0 + 1 = 2.

%p a:= n -> convert(convert(11*n,base,10),`+`):

%p seq(a(n),n=0..100); # _Robert Israel_, Aug 01 2014

%t Table[Plus@@IntegerDigits[11n], {n, 0, 99}]

%o (PARI) a(n) = sumdigits(11*n); \\ _Michel Marcus_, Aug 03 2014

%Y Cf. A008593, A007953.

%K nonn,base,easy

%O 0,2

%A _Alonso del Arte_, Jul 27 2014