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A181802 Triangle read by rows: T(n,k) is k-th smallest divisor of n that is highly composite (A002182). 6

%I #6 Mar 30 2012 17:27:19

%S 1,1,2,1,1,2,4,1,1,2,6,1,1,2,4,1,1,2,1,1,2,4,6,12,1,1,2,1,1,2,4,1,1,2,

%T 6,1,1,2,4,1,1,2,1,1,2,4,6,12,24,1,1,2,1,1,2,4,1,1,2,6,1,1,2,4,1,1,2,

%U 1,1,2,4,6,12,36,1,1,2,1,1,2,4,1,1,2,6,1,1,2,4,1,1,2,1,1,2,4,6,12,24,48

%N Triangle read by rows: T(n,k) is k-th smallest divisor of n that is highly composite (A002182).

%C Row n contains A181801(n) numbers. T(n,k) * A180803(n, A181801(n)-k+1) = n.

%C Row n is identical to row (n+12) if n is not a multiple of 12.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/HighlyCompositeNumber.html">Highly composite number</a>

%F T(n,k) = n/(A180803(n, A181801(n)-k+1)).

%e First rows read: 1; 1,2; 1; 1,2,4; 1; 1,2,6; 1; 1,2,4; 1; 1,2; 1; 1,2,4,6,12;...

%e 8 has four divisors, of which three (1, 2 and 4) are members of A002182. Row 8 therefore reads 1, 2, 4.

%Y See also A181804, A181805, A181806, A181807.

%K nonn,tabf

%O 1,3

%A _Matthew Vandermast_, Nov 27 2010

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Last modified August 17 21:11 EDT 2024. Contains 375227 sequences. (Running on oeis4.)