A202106 Smallest prime p such that 4n^2+p is prime.

3, 3, 5, 3, 3, 5, 3, 7, 7, 19, 3, 11, 7, 3, 7, 7, 7, 5, 3, 7, 13, 13, 13, 5, 3, 3, 11, 31, 7, 7, 3, 3, 7, 13, 3, 5, 3, 3, 5, 73, 13, 13, 37, 13, 11, 3, 3, 5, 19, 7, 23, 31, 3, 13, 7, 3, 5, 7, 7, 7, 3, 7, 5, 37, 3, 7, 3, 7, 7, 3, 13, 7, 3, 7, 11, 13, 3, 23, 3

Offset

1,1

Links

Table of n, a(n) for n=1..79.

Example

n=1: 4+3=7 prime, n=2: 16+3=19 prime,
n=3: 36+5=41 prime, n=10: 400+19=419 prime.

Mathematica

Table[p=3; While[!PrimeQ[4n^2+p], p=NextPrime[p]]; p, {n, 100}]

Crossrefs

Sequence in context: A054906 A269733 A138479 * A136019 A242017 A063714

Adjacent sequences: A202103 A202104 A202105 * A202107 A202108 A202109

Keyword

nonn

Author

Zak Seidov, Dec 11 2011

Status

approved