A284662 Number of harmonic seed numbers (A035527) whose largest prime factor is the n-th odd prime (A065091).

1, 1, 3, 0, 5, 2, 19, 0, 0, 37, 10, 19, 21, 0, 0, 0, 89, 143, 84, 97, 26, 0, 127, 283

Offset

1,3

Links

Table of n, a(n) for n=1..24.

Yusuke Chishiki, Takeshi Goto, and Yasuo Ohno, On the largest prime divisor of an odd harmonic number, Mathematics of Computation, Vol. 76, No. 259 (2007), pp. 1577-1587.

Example

There are 3 harmonic seed numbers whose largest prime factor is A065091(3) = 7 (28, 672 and 30240), thus a(3) = 3.

Crossrefs

Cf. A035527.

Sequence in context: A177886 A011293 A181884 * A292031 A201565 A088191

Adjacent sequences: A284659 A284660 A284661 * A284663 A284664 A284665

Keyword

nonn,more

Author

Amiram Eldar, Mar 31 2017

Status

approved