A089362 Numbers n such that n^2 - 5n + 5 is prime.

5, 6, 7, 8, 9, 11, 12, 13, 14, 16, 18, 19, 22, 23, 24, 27, 29, 31, 33, 34, 38, 41, 42, 44, 47, 48, 49, 51, 53, 56, 57, 58, 59, 62, 63, 67, 68, 69, 71, 73, 79, 86, 88, 89, 92, 96, 97, 99, 103, 104, 106, 117, 118, 123, 128, 129, 133, 134, 137, 141, 143, 144, 147, 148, 151, 152, 156, 157, 158, 161, 162, 163, 166, 167, 172

Offset

1,1

References

M. Cerasoli, F. Eugeni and M. Protasi, Elementi di Matematica Discreta, Bologna 1988.

Emanuele Munarini and Norma Zagaglia Salvi, Matematica Discreta, UTET, CittaStudiEdizioni, Milano 1997.

Links

Table of n, a(n) for n=1..75.

Formula

a(n) = A002328(n)+2.

Prog

(PARI) is(n)=isprime(n^2-5*n+5) \\ Charles R Greathouse IV, Jun 13 2017

Crossrefs

Cf. A002328.

Sequence in context: A023379 A003667 A138469 * A333532 A121537 A285219

Adjacent sequences: A089359 A089360 A089361 * A089363 A089364 A089365

Keyword

easy,nonn

Author

Giovanni Teofilatto, Dec 27 2003

Extensions

Corrected and extended by Georg Fischer, Jun 20 2020

Status

approved