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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
OFFSET
1,1
COMMENTS
Generalization of A005385. Can be called 210-safe primes.
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
KEYWORD
nonn
AUTHOR
STATUS
approved