A080185 Primes p such that 5 is the largest of all prime factors of the numbers between p and the next prime (cf. A052248).

7, 29, 59, 149, 179, 239, 269, 599, 809, 1619, 2999, 4049, 4799, 8999, 9719, 15359, 21599, 23039, 33749, 138239, 179999, 281249, 345599, 737279, 3455999, 6143999, 6560999, 10124999, 13668749, 15551999, 17495999, 20995199, 22118399, 23999999

Offset: 1

Author

Klaus Brockhaus, Feb 10 2003

Keywords

• nonn

Comments

The sequence consists of 7 and the lesser of twin primes q (A001359) such that q+1 is 5-smooth (A051037) but not 3-smooth (A003586, A080193).

Examples

			7 is a term since 8 = 2^3, 9 = 3^3, 10 = 2*5 are the numbers between 7 and the next prime 11; 149 is a term since 150 = 2*3*5^2 is the only number between 149 and the next prime 151.
		

Links

• Amiram Eldar, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A052248, A001359, A051037, A003586, A080193.

Programs

PARI

{forprime(p=2,24000000,q=nextprime(p+1); m=0; j=p+1; while(j