%I A127375
%S A127375 1,3,0,4,1,0,7,0,1,0,6,1,1,1,0,12,0,0,1,0,8,1,1,1,1,1,0,15,0,3,0,1,0,1,
%T A127375 0,13,4,0,1,1,0,1,1,0,18,2,3,2,0,0,1,0,1,0
%N A127375 Triangle, row sums = sum of gcd(k,n) for 1<=k<=n; left column = sigma(n).
%C A127375 Left column = sigma(n), A000203: (1, 3, 4, 7, 6, 12...); row sums = A018804,
sum of gcd(k,n) for 1<=k<=n: (1,3, 5, 8, 9, 15, 13,..)
%F A127375 A126988 * A054521, as infinite lower triangular matrices.
%e A127375 First few rows of the triangle are:
%e A127375 1;
%e A127375 3, 0;
%e A127375 4, 1, 0;
%e A127375 7, 0, 1, 0;
%e A127375 6, 1, 1, 1, 0;
%e A127375 12, 2, 0, 0, 1, 0;
%e A127375 8, 1, 1, 1, 1, 1, 0;
%e A127375 ...
%Y A127375 Cf. A126988, A054521, A018804, A000203.
%Y A127375 Sequence in context: A060034 A035544 A129718 this_sequence A138376 A077140
A003815
%Y A127375 Adjacent sequences: A127372 A127373 A127374 this_sequence A127376 A127377
A127378
%K A127375 nonn,tabl
%O A127375 1,2
%A A127375 Gary W. Adamson (qntmpkt(AT)yahoo.com), Jan 12 2007
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