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A057633 Initial prime in first sequence of n primes congruent to 5 modulo 8. 0
5, 389, 2213, 45013, 73133, 1319861, 3250469, 29662253, 35677501, 101341613, 12664911341, 12664911341, 124809839701, 132932904029, 1181960064853 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

LINKS

J. K. Andersen, Consecutive Congruent Primes.

EXAMPLE

a(3) = 2213 because this number is the first in a sequence of 3 consecutive primes all of the form 8n + 5.

MATHEMATICA

NextPrime[ n_Integer ] := Module[ {k = n + 1}, While[ ! PrimeQ[ k ], k++ ]; Return[ k ] ]; PrevPrime[ n_Integer ] := Module[ {k = n - 1}, While[ ! PrimeQ[ k ], k-- ]; Return[ k ] ]; p = 0; Do[ a = Table[ -1, {n} ]; k = Max[ 1, p ]; While[ Union[ a ] != {5}, k = NextPrime[ k ]; a = Take[ AppendTo[ a, Mod[ k, 8 ] ], -n ] ]; p = NestList[ PrevPrime, k, n ]; Print[ p[[ -2 ] ] ]; p = p[[ -1 ] ], {n, 1, 9} ]

CROSSREFS

Sequence in context: A100474 A152438 A060506 * A193126 A006700 A079011

Adjacent sequences:  A057630 A057631 A057632 * A057634 A057635 A057636

KEYWORD

nonn

AUTHOR

Robert G. Wilson v (rgwv(AT)rgwv.com), Oct 10 2000

EXTENSIONS

More terms from Jens Kruse Andersen (jens.k.a(AT)get2net.dk), May 28 2006

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Last modified February 17 11:46 EST 2012. Contains 206011 sequences.