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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. 5

%I #4 Mar 30 2012 17:29:20

%S 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 27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,45,48,44,46,47,49,

%U 50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72

%N 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 Variation of A077172.

%e Triangle begins:

%e 2

%e 3,4

%e 1,5,6

%e 7,8,9,10

%e 11,12,13,14,16

%e 15,17,18,19,20,21

%e 22,23,24,25,26,27,28

%e 29,30,31,32,33,34,35,36

%e 37,38,39,40,41,42,43,45,48

%e 44,46,47,49,50,51,52,53,54,55

%e 56,57,58,59,60,61,62,63,64,65,66

%e 67,68,69,70,71,72,73,74,75,76,77,80

%e 78,79,81,82,83,84,85,86,87,88,89,90,91

%Y Cf. A101175, A101176, A101177, A101178, A101179.

%Y Cf. A093451.

%K nonn,tabl

%O 1,1

%A _Ray Chandler_, Dec 03 2004

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Last modified March 28 10:55 EDT 2024. Contains 371241 sequences. (Running on oeis4.)