A072828 Primes p such that p+1 is a highly composite number.

3, 5, 11, 23, 47, 59, 179, 239, 359, 719, 839, 1259, 5039, 7559, 10079, 55439, 110879, 166319, 665279, 1081079, 1441439, 6486479, 32432399, 61261199, 698377679, 735134399, 1102701599, 1396755359, 2205403199, 20951330399, 41902660799

Offset

1,1

Links

Amiram Eldar, Table of n, a(n) for n = 1..441 (terms below 10^1000; terms 1..300 from T. D. Noe)

Benny Lim, Prime Numbers Generated From Highly Composite Numbers, Parabola Magazine, volume 54, issue 3, 2018.

Formula

a(n) == 2 (mod 3) for n > 1 (because highly composite numbers > 4 are == 0 (mod 3); see A002182). - Jonathan Sondow, Nov 05 2015

a(n) = A002182(A306588(n)) - 1. - Amiram Eldar, Dec 03 2020

Example

47 is a term because it is prime and also 47+1=48 is a highly composite number.

Crossrefs

Cf. A002182, A068507, A072826, A214873, A306588.

Sequence in context: A260239 A023223 A106086 * A290114 A032803 A335883

Adjacent sequences: A072825 A072826 A072827 * A072829 A072830 A072831

Keyword

nonn

Author

Shyam Sunder Gupta, Jul 21 2002

Status

approved