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A101174 Triangle formed by grouping the natural numbers so that the n-th row contains n numbers whose product has exactly n prime divisors, minimizing (1) final term of row and (2) product of terms of row.

%I A101174 #4 Mar 30 2012 17:29:20
%S A101174 2,3,4,1,5,6,7,8,9,10,11,12,13,14,16,15,17,18,19,20,21,22,23,24,25,26,
%T A101174 27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,45,48,44,46,47,49,
%U A101174 50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72
%N A101174 Triangle formed by grouping the natural numbers so that the n-th row contains n numbers whose product has exactly n prime divisors, minimizing (1) final term of row and (2) product of terms of row.
%C A101174 Variation of A077172.
%e A101174 Triangle begins:
%e A101174 2
%e A101174 3,4
%e A101174 1,5,6
%e A101174 7,8,9,10
%e A101174 11,12,13,14,16
%e A101174 15,17,18,19,20,21
%e A101174 22,23,24,25,26,27,28
%e A101174 29,30,31,32,33,34,35,36
%e A101174 37,38,39,40,41,42,43,45,48
%e A101174 44,46,47,49,50,51,52,53,54,55
%e A101174 56,57,58,59,60,61,62,63,64,65,66
%e A101174 67,68,69,70,71,72,73,74,75,76,77,80
%e A101174 78,79,81,82,83,84,85,86,87,88,89,90,91
%Y A101174 Cf. A101175, A101176, A101177, A101178, A101179.
%Y A101174 Cf. A093451.
%K A101174 nonn,tabl
%O A101174 1,1
%A A101174 _Ray Chandler_, Dec 03 2004