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%I #11 Jul 27 2017 03:07:36
%S 1,4,9,22,40,62,88,118,152,190,253,322,397,478,565,658,757,862,973,
%T 1090,1213,1342,1477,1618,1765,1918,2077,2242,2413,2590,2773,2986,
%U 3246,3514,3790,4074,4366,4666,4974,5290,5614,5946,6286,6634,6990,7354,7726,8106
%N Write the natural numbers as an infinite sequence of digits, starting at the left; a(n) is the subset (i.e., the position in this sequence of the "counting digits") of the first digit of the n-th square.
%e integers : 1234567891011121314151617...
%e 1st digit : x x x x
%e positions : 1 4 9 22
%o (PARI) a(n) = 1+ sum(k=1, n^2-1, #digits(k)); \\ _Michel Marcus_, Jul 27 2017
%Y Cf. A103575.
%K base,easy,nonn
%O 1,2
%A _Alexandre Wajnberg_, Apr 25 2005
%E More terms from _Joshua Zucker_, Jun 21 2006
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