%I #5 Jul 30 2015 23:02:06
%S 9,18,19,27,28,37,39,46,48,56,59,66,69,78,82,88,92,100,105,111,116,
%T 125,131,137,143,152,159,167,175,177,185,193,202,204,205,205,205,206,
%U 206,211,212,213,214,215,216,222,223,225,230,231,234,235,236,239,246,247
%N First differences give the same sequence written as a string of individual digits.
%e 9.18.19.27.28.37.39.46.48.56 ... <- sequence
%e .9..1..8..1..9..2..7..2..8 ... <- first differences are the sequence's digits.
%t a[1] = 9; a[n_] := a[n] = a[n - 1] + Flatten[ Table[ IntegerDigits[ a[i]], {i, n - 1}]][[n - 1]]; Table[ a[n], {n, 56}] (* _Robert G. Wilson v_, Jun 15 2005 *)
%Y Cf. A100787, A107974, A107975, A107976, A107977 for "seeds" 1, 3, 5, 7 and 9.
%K base,easy,nonn
%O 1,1
%A _Eric Angelini_, Jun 12 2005
%E Edited and extended by _Robert G. Wilson v_, Jun 15 2005
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