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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
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
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
Sequence in context: A274859 A137855 A113143 * A371823 A373778 A110971
KEYWORD
nonn,tabf
AUTHOR
Matthew Vandermast, Nov 27 2010
STATUS
approved