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Sum of the digits of LookAndSay(n).
0

%I #2 Feb 11 2014 19:05:40

%S 2,3,4,5,6,7,8,9,10,3,3,5,6,7,8,9,10,11,12,4,5,4,7,8,9,10,11,12,13,5,

%T 6,7,5,9,10,11,12,13,14,6,7,8,9,6,11,12,13,14,15,7,8,9,10,11,7,13,14,

%U 15,16,8,9,10,11,12,13,8,15,16,17,9,10,11,12,13,14,15,9,17,18,10,11,12,13

%N Sum of the digits of LookAndSay(n).

%e LookAndSay(23) = 1213, the sum of whose digits = 7, so a(23) = 7.

%t lookandsay[n_] := Module[{r, d, f, i, l, k}, r = ""; d = IntegerDigits[n]; While[d != {}, f = First[d]; i = 2; l = Length[d]; While[i <= l && d[[i]] == f, i = i + 1]; k = i - 1; r = r <> ToString[k]; r = r <> ToString[f]; d = Drop[d, k]]; ToExpression[r]]; t = Table[Apply[Plus, IntegerDigits[lookandsay[i]]], {i, 1, 100}]

%K base,nonn

%O 1,1

%A _Joseph L. Pe_, Feb 02 2003