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%I #15 Jul 22 2017 08:51:23
%S 1,1,1,2,3,2,3,4,4,2,4,7,8,6,4,5,6,9,4,9,2,6,9,10,13,14,6,6,7,8,15,8,
%T 19,4,13,2,8,13,13,16,23,15,19,10,7,9,10,16,12,26,7,25,7,12,3,10,13,
%U 23,24,31,18,31,25,21,12,10,11,12,21,15,36,11,38,19,25,11,21,3,12,19,22,24,39
%N Table (read by antidiagonals) where t(1,1)=1, t(m,n) = number of terms above and to the left of t(m,n) (i.e., number of t(k,j)'s, where 1 <= k <= m, 1 <= j <= n, excluding the t(m,n) case itself) which either divide m or are coprime to n.
%H Vincenzo Librandi, <a href="/A124525/b124525.txt">Table of n, a(n) for n = 1..2485</a>
%e The first 4 columns and first 6 rows (excluding t(6,4)) of the table are:
%e 1, 1, 2, 2
%e 1, 3, 4, 6
%e 2, 4, 8, 4
%e 3, 7, 9, 13
%e 4, 6, 10, 8
%e 5, 9, 15
%e The number of these terms which either divide 6 or are coprime to 4 is 16 (the odd integers, the 2's and the 6's). So t(6,4) = 16.
%t t[1, 1] = 1;t[m_, n_] := t[m, n] = Block[{c = 0},Do[ Do[ If[k == m && j == n, Continue[]];If[Mod[m, t[k, j]] == 0 || GCD[t[k, j], n] == 1, c++ ];, {j, n}];, {k, m}];c];Flatten[Table[t[d + 1 - i, i], {d, 13}, {i, d}]] (* _Ray Chandler_, Nov 11 2006 *)
%Y Cf. A124524.
%K nonn,tabl
%O 1,4
%A _Leroy Quet_, Nov 04 2006
%E Extended by _Ray Chandler_, Nov 11 2006