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A023996 Triangle of numbers T(n,k), where T(n,k) is the number of sets S = {a_1, a_2, ..., a_k}, with 1 < a_i < a_j <= n such that no a_j divides the product of all the others.

%I A023996 #10 Jun 18 2019 03:32:04
%S A023996 1,1,1,1,2,1,1,3,2,1,4,5,2,1,5,7,3,1,6,12,10,3,1,7,16,15,5,1,8,22,24,
%T A023996 9,1,9,28,34,14,1,10,37,62,48,14,1,11,43,74,58,17,1,12,54,117,132,75,
%U A023996 17,1,13,64,151,182,108,25,1,14,75,184,224,132,30,1,15,86
%N A023996 Triangle of numbers T(n,k), where T(n,k) is the number of sets S = {a_1, a_2, ..., a_k}, with 1 < a_i < a_j <= n such that no a_j divides the product of all the others.
%H A023996 Sean A. Irvine, <a href="/A023996/b023996.txt">Table of n, a(n) for n = 0..586</a> (rows 0..55 flattened)
%H A023996 Sean A. Irvine, <a href="https://github.com/archmageirvine/joeis/blob/master/src/irvine/oeis/a023/A023996.java">Java program</a> (github)
%e A023996 From _Sean A. Irvine_, Jun 17 2019: (Start)
%e A023996   1;
%e A023996   1,  1;
%e A023996   1,  2,  1;
%e A023996   1,  3,  2;
%e A023996   1,  4,  5,  2;
%e A023996   1,  5,  7,  3;
%e A023996   1,  6, 12, 10,  3;
%e A023996   ... (End)
%Y A023996 Cf. A023995.
%K A023996 tabf,nonn
%O A023996 0,5
%A A023996 Lionel Levine (levine(AT)ultranet.com)