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

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, 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, 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

Offset

1,3

Comments

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

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

Links

Table of n, a(n) for n=1..100.

Eric Weisstein's World of Mathematics, Highly composite number

Formula

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

Example

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

Crossrefs

See also A181804, A181805, A181806, A181807.

Sequence in context: A274859 A137855 A113143 * A371823 A373778 A110971

Adjacent sequences: A181799 A181800 A181801 * A181803 A181804 A181805

Keyword

nonn,tabf

Author

Matthew Vandermast, Nov 27 2010

Status

approved