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A247880 For bases b = 2, 3, ..., n, let the base-b expansion of n be [c_{1,b} c_{2,b} .. c_{r_b,b}], with the most significant "digit" on the left, 0 <= c_{i,b} < b, and c_{1,b} != 0; then a(n) is the number whose base-n expansion is the sum of all those expansions, regarding the c_{i,j} as integers mod n.

%I A247880 #41 Mar 25 2015 13:04:49
%S A247880 2,7,25,44,75,106,584,885,1213,1595,2201,2758,3419,4176,66388,84490,
%T A247880 106391,131905,162181,196924,236973,282814,348325,409728,478356,
%U A247880 573416,662184,759951,868308,987703,33592007,39176497,45480263,52570673,60522786,69405129
%N A247880 For bases b = 2, 3, ..., n, let the base-b expansion of n be [c_{1,b} c_{2,b} .. c_{r_b,b}], with the most significant "digit" on the left, 0 <= c_{i,b} < b, and c_{1,b} != 0; then a(n) is the number whose base-n expansion is the sum of all those expansions, regarding the c_{i,j} as integers mod n.
%C A247880 The base-n expansion of a(n) is the sum of the expansions of n in bases n, n-1, ..., 3, 2, regarding all the coefficients as numbers in the range 0 to n-1.
%H A247880 Lars Blomberg, <a href="/A247880/b247880.txt">Table of n, a(n) for n = 2..200</a>
%e A247880 For n=4, we first write 4 in bases 4, 3 and 2: 10, 11, 100, whose sum is the base 4 number 121, which is 25 in base 10.
%e A247880 For n=6, we get 110, 20, 12, 11, 10, whose sum (as base-6 numbers) is 203_6 = 75_10, so a(6) = 75.
%o A247880 (PARI) a(n) = sum(b=2, n, my(d = digits(n, b)); sum(k=1, #d, d[k]*n^(#d-k));); \\ _Michel Marcus_, Mar 19 2015
%Y A247880 Cf. A247873, A247878.
%K A247880 nonn,base,easy
%O A247880 2,1
%A A247880 _Talha Ali_, Sep 25 2014
%E A247880 Definition revised by _N. J. A. Sloane_, Sep 27 2014
%E A247880 a(7)-a(37) from _Lars Blomberg_, Feb 28 2015