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A051648 Primes of form 210*p + 1 where p is a prime. 1
421, 631, 1051, 1471, 2311, 2731, 3571, 4831, 6091, 9871, 11131, 12391, 14071, 15331, 17431, 18691, 21211, 28771, 29191, 32971, 34231, 37591, 38011, 40111, 40531, 46831, 48091, 52711, 56911, 58171, 59011, 65731, 66571, 72871, 73291 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Generalization of A005385. Can be called 210-safe primes.

LINKS

Table of n, a(n) for n=1..35.

FORMULA

A002110(4)*p + 1 = 210*p + 1 (prime).

EXAMPLE

631 is in the sequence because 631 = 210*p + 1, where p=3.

MATHEMATICA

Select[Table[210n+1, {n, Prime[Range[100]]}], PrimeQ] (* Harvey P. Dale, Dec 25 2016 *)

CROSSREFS

Cf. A005384, A005385, A007693, A002110.

Sequence in context: A159589 A031784 A268859 * A217497 A333640 A146358

Adjacent sequences:  A051645 A051646 A051647 * A051649 A051650 A051651

KEYWORD

nonn

AUTHOR

Labos Elemer

STATUS

approved

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Last modified June 1 03:14 EDT 2020. Contains 334758 sequences. (Running on oeis4.)