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A057634
Initial prime in first sequence of n primes congruent to 7 modulo 8.
0
7, 359, 1823, 79063, 272863, 989647, 10604519, 10604519, 309202951, 309202951, 1383423311, 21120585463, 534956098463, 534956098463, 534956098463, 925195153703, 74587805307479
OFFSET
1,1
EXAMPLE
a(4) = 79063 because this number is the first in a sequence of 4 consecutive primes all of the form 8n + 7.
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 ] != {7}, k = NextPrime[ k ]; a = Take[ AppendTo[ a, Mod[ k, 8 ]], -n ]]; p = NestList[ PrevPrime, k, n ]; Print[ p[[ -2 ] ]]; p = p[[ -1 ]], {n, 1, 8} ] a(9) > 115647000.
CROSSREFS
Sequence in context: A185062 A067556 A082098 * A203706 A145181 A221353
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Oct 10 2000
EXTENSIONS
More terms from Jens Kruse Andersen, May 28 2006
a(17) from Giovanni Resta, Aug 04 2013
STATUS
approved