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%I #8 Jun 29 2014 22:29:20
%S 1,3,2,6,5,4,1,9,8,7,2,1,1,1,0,5,1,4,1,3,1,1,8,1,7,1,6,1,2,2,2,1,2,0,
%T 2,9,7,2,6,2,5,2,4,2,3,2,3,1,3,0,3,9,2,8,2,3,7,3,6,3,5,3,4,3,3,3,4,3,
%U 4,2,4,1,4,0,4,9,3,8,0,5,9,4,8,4,7,4,6,4,5,4,4,7,5,6,5,5,5,4,5,3,5,2,5,1,5
%N Take the sequence of almost-natural numbers (A007376) and reverse successive subsequences of lengths 1,2,3,4,...
%C See the table in A244425 and read the table by the other antidiagonal.
%t a[n_] := Block[{m = 0, d = n, i = 1, l, p}, While[m <= d, l = m; m = 9 i*10^(i - 1) + l; i++]; i--; p = Mod[d - l, i]; q = Floor[(d - l)/i] + 10^(i - 1); If[ p != 0, IntegerDigits[q][[p]], Mod[q - 1, 10]]]; Table[ a[ Ceiling[(Sqrt[ 8n + 1] - 1)/2]^2 - n + 1], {n, 105}]
%Y Cf. A007376, A033307, A038722, A244425.
%K nonn,base,tabl
%O 1,2
%A _Robert G. Wilson v_, Jun 27 2014