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A023333 Numbers n such that n remains prime through 5 iterations of function f(x) = 2x + 7. 1
14723, 20123, 54713, 109433, 594653, 604883, 676493, 759953, 847103, 935843, 1035743, 1049603, 1079033, 1099823, 1222253, 1263323, 1499153, 1754033, 1835003, 1893173, 2017283, 2071493, 2099213, 2199653, 2895743, 2998313, 3389693, 4133663 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

n, 2*n+7, 4*n+21, 8*n+49, 16*n+105 and 32*n+217 are primes. - Vincenzo Librandi, Aug 04 2010

LINKS

John Cerkan, Table of n, a(n) for n = 1..10000

FORMULA

a(n) == 23 (mod 30). - John Cerkan, Oct 10 2016

PROG

(MAGMA) [n: n in [1..5000000] | IsPrime(n) and IsPrime(2*n+7) and IsPrime(4*n+21) and IsPrime(8*n+49) and IsPrime(16*n+105) and IsPrime(32*n+217)] // Vincenzo Librandi, Aug 04 2010

CROSSREFS

Subsequence of A023206, A023244, A023275, A023305, and A105760.

Sequence in context: A256839 A015312 A219068 * A249464 A209513 A178587

Adjacent sequences:  A023330 A023331 A023332 * A023334 A023335 A023336

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified January 20 17:32 EST 2018. Contains 297961 sequences.