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A081519 Sum of terms in row n of A081520.

%I A081519 #9 May 21 2015 14:14:32
%S A081519 1,3,10,13,51,24,148,57,109,77,606,100,1015,161,226,241,2313,231,3250,
%T A081519 318,493,425,5820,415,1501,605,1054,664,11775,593,14416,993,1344,1061,
%U A081519 1896,946,24643,1337,1931,1302,33621,1204,38830,1737,2124,1985,50808
%N A081519 Sum of terms in row n of A081520.
%C A081519 a(p) = p^2*(p-1)/2 + 1, p is prime.
%C A081519 a(p^k) = p^(k+1)*(p^k-1)/2 + 1 if p is prime and k >= 1. - _Robert Israel_, May 21 2015
%H A081519 Ivan Neretin, <a href="/A081519/b081519.txt">Table of n, a(n) for n = 1..1000</a>
%p A081519 A:= proc(n) local L;
%p A081519   L:= select(t->igcd(t,n)>1,[$1..n^2])[1 .. n-1];
%p A081519   1+convert(L,`+`)
%p A081519 end proc:
%p A081519 seq(A(n),n=1..100); # _Robert Israel_, May 21 2015
%t A081519 Table[Plus @@ Join[{1}, Select[Range[n^2], GCD[n, #] > 1 &, n - 1]], {n, 1, 47}](* _Ivan Neretin_, May 21 2015 *)
%Y A081519 Cf. A081518, A081520.
%K A081519 nonn
%O A081519 1,2
%A A081519 _Amarnath Murthy_, Mar 27 2003
%E A081519 More terms from _Ryan Propper_, Nov 05 2005