A074396 a(n) = 10 - (p mod 10), where p is the n-th prime congruent to 1 (mod 4) for which p+2 is also prime.

5, 3, 1, 9, 9, 3, 1, 3, 1, 9, 9, 9, 1, 3, 9, 1, 9, 3, 9, 1, 9, 1, 3, 1, 9, 9, 3, 9, 3, 1, 3, 9, 1, 9, 3, 1, 9, 1, 3, 1, 1, 9, 1, 3, 1, 1, 9, 3, 9, 9, 3, 1, 9, 1, 3, 3, 1, 9, 3, 9, 9, 3, 3, 1, 9, 1, 9, 3, 9, 3, 9, 3, 9, 1, 1, 3, 1, 1, 1, 1, 9, 9, 1, 1, 3, 1, 3, 3, 1, 1, 1, 3, 3, 3, 9, 1, 9, 9, 9, 3, 9, 1, 3, 3, 1

Offset

1,1

Links

Table of n, a(n) for n=1..105.

Example

The first 5 such primes are 5, 17, 29, 41, 101. For these, 10 - (p mod 10) is 5, 3, 1, 9, 9.

Mathematica

10-Mod[ #, 10]&/@Select[Prime/@Range[1500], PrimeQ[ #+2]&&Mod[ #, 4]==1&]

Crossrefs

Cf. A071695.

Sequence in context: A262674 A011363 A021192 * A229958 A157891 A173644

Adjacent sequences: A074393 A074394 A074395 * A074397 A074398 A074399

Keyword

nonn

Author

Roger L. Bagula, Sep 24 2002

Extensions

Edited by Dean Hickerson, Oct 09 2002

Status

approved