A277879 Smallest prime r such that p = (q + r + 1)/r, where p = prime(n) and q = A277878(n).

2, 2, 2, 2, 2, 2, 3, 2, 3, 2, 2, 2, 2, 3, 2, 3, 3, 2, 2, 5, 3, 2, 3, 2, 2, 5, 2, 11, 2, 2, 3, 2, 19, 3, 3, 2, 5, 2, 5, 23, 2, 2, 2, 3, 3, 2, 2, 3, 3, 2, 11, 2, 2, 5, 2, 23, 3, 3, 3, 2, 5, 7, 2, 5, 2, 2, 7, 2, 13, 5, 5, 3, 2, 5, 11, 3, 3, 5, 3, 5, 2, 2, 2, 11, 2

Offset

2,1

Comments

Rassias's conjecture is the claim that q and r exist for every p.

Links

Table of n, a(n) for n=2..86.

Wikipedia, Rassias' conjecture.

Prog

(PARI) a(n) = my(t=prime(n)-1); forprime(r=2, oo, if(isprime(r*t-1), return(r))); \\ Jinyuan Wang, Jul 25 2021

Crossrefs

Cf. A277878.

Sequence in context: A174273 A108128 A081326 * A257071 A332025 A212300

Adjacent sequences: A277876 A277877 A277878 * A277880 A277881 A277882

Keyword

nonn

Author

Felix Fröhlich, Nov 03 2016

Extensions

Terms corrected by and more terms from Jinyuan Wang, Jul 25 2021

Status

approved