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%I #12 Oct 31 2019 11:49:43
%S 1,2,3,6,4,5,30,12,8,7,210,60,18,10,9,2310,420,90,24,14,11,30030,4620,
%T 630,120,36,16,13,510510,60060,6930,840,150,42,20,15,9699690,1021020,
%U 90090,9240,1050,180,48,22,17,223092870,19399380,1531530,120120,11550
%N Table read by antidiagonals: row n contains the positive integers (in order) which are coprime to the n-th prime and do not occur in earlier rows.
%C Row n, for n >= 2, contains the multiples of (product{k=1 to n-1} p(k)) that are coprime to p(n), where p(k) is the k-th prime. The concatenated sequence is a permutation of the positive integers.
%F T(n,m) = A002110(n-1)*A125704(n,m). - _Ray Chandler_, Feb 07 2007
%e The beginning of the table:
%e 1,3,5,7,9,11,...
%e 2,4,8,10,14,16,20,...
%e 6,12,18,24,36,...
%e 30,60,90,120,150,...
%e 210,420,630,840,...
%t f[n_, m_] := Block[{p = Prime[n], x = Product[Prime[i], {i, n - 1}], k = 0, c = m},While[c > 0,k += x;While[GCD[k, p] > 1, k += x];c--;];k];Table[f[d + 1 - m, m], {d, 10}, {m, d}] // Flatten (* _Ray Chandler_, Feb 07 2007 *)
%K nonn,tabl
%O 1,2
%A _Leroy Quet_, Jan 31 2007
%E Extended by _Ray Chandler_, Feb 07 2007