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%I #2 Mar 30 2012 17:31:12
%S 1,3,0,2,2,2,1,0,1,0,1,1,3,1,2,1,2,2,4,3,3,3,4,4,3,0,0,0,4,1,2,0,1,2,
%T 2,3,2,1,3,3,2,2,1,1,4,2,0,2,2,1,4,0,4,3,3,2,3,3,4,4,2,4,2,3,4,3,4,0,
%U 1,1,0,1,0,1,1,0,1,1,1,1,1,2,1,1,1,2,4,2,1,1,2,2,3,1,1,3,1,4,1,1,4,1,4,1,2
%N Write the natural numbers in base 5 in a triangle with k digits in the k-th row, as shown below. Sequence gives the leading diagonal.
%C 1
%C 23
%C 410
%C 1112
%C 13142
%C 021222...
%t t = Flatten[IntegerDigits[Range[1500], 5]]; t[[Table[n(n + 1)/2, {n, 105}]]]
%Y Cf. A104606, A104607, A104608, A104610, A104611, A104612, A104613, A091425, A104614, A104615, A104616, A104617, A104618, A104619, A104620.
%K base,nonn
%O 1,2
%A _Robert G. Wilson v_, Mar 16 2005