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First differences give the same sequence written as a string of individual digits.
6

%I #5 Jul 30 2015 23:01:50

%S 7,14,15,19,20,25,26,35,37,37,39,44,46,52,55,60,63,70,73,80,83,92,96,

%T 100,104,110,115,117,122,127,133,133,139,142,149,149,156,159,167,167,

%U 175,178,187,189,198,204,205,205,205,206,206,210,211,212,212,213,214

%N First differences give the same sequence written as a string of individual digits.

%C Cf. A100787, A107974, A107975, A107976, A107977 for "seeds" 1, 3, 5, 7 and 9.

%e 7.14.15.19.20.25.26.35.37.37... <- sequence

%e .7..1..4..1..5..1..9..2..0... <- first differences = the sequence's digits

%t a[1] = 7; a[n_] := a[n] = a[n - 1] + Flatten[ Table[ IntegerDigits[ a[i]], {i, n - 1}]][[n - 1]]; Table[ a[n], {n, 60}] (* _Robert G. Wilson v_, Jun 15 2005 *)

%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