A181807 Number of divisors of A181806(n) that are highly composite (A002182).

1, 2, 3, 5, 6, 7, 8, 10, 11, 14, 19, 20, 21, 22, 23, 24, 25, 28, 31, 32, 33, 35, 38, 39, 41, 48, 49, 52, 53, 57, 59, 65, 67, 69, 77, 81, 82, 86, 91, 94, 103, 105, 107, 114, 118, 122, 125, 131, 132, 135, 141, 142, 144, 145, 154, 157, 160, 163, 166, 171, 175, 180

Offset

1,2

Comments

Also, length of row A181806(n) in triangles A181802 and A181803.

Links

David A. Corneth, Table of n, a(n) for n = 1..153

A. Flammenkamp, List of the first 1200 highly composite numbers

Eric Weisstein's World of Mathematics, Highly composite number

Formula

a(n) = A181801(A181806(n)).

Example

A181806(4) = 12 has exactly five divisors (namely, 1, 2, 4, 6 and 12) that are members of A002182.  Hence, a(4) = 5.

Crossrefs

Cf. A002182, A181801, A181802, A181803, A181806.

Sequence in context: A368999 A336487 A028765 * A059870 A179813 A191914

Adjacent sequences: A181804 A181805 A181806 * A181808 A181809 A181810

Keyword

nonn

Author

Matthew Vandermast, Nov 27 2010

Extensions

More terms from Amiram Eldar, Aug 29 2019 (calculated from the b-file at A181806)

Status

approved