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A207825
Primes p such that (p+k)/(k+1) is a prime number for k = 1,...,6.
3
5516281, 18164161, 51755761, 175472641, 322030801, 668745001, 859992841, 1163859481, 1566071641, 3662011081, 4285181881, 4609064881, 4630772161, 5329427041, 5601138481, 5934191761, 7123263841, 7321991041, 7391371681, 7969001041, 8735990761
OFFSET
1,1
COMMENTS
The subsequence of p in A208455 such that (p+6)/7 is a prime.
Also, the subsequence of terms of A071369 which end in the digit "1".
All terms are of the form 2520m+1. The m-values are listed in A208549.
FORMULA
a(n) = A208549(n)*2520 + 1.
PROG
(PARI) {my(p=1); until(, isprime(p+=2520) || next; for(j=2, 7, isprime(p\j+1)||next(2)); print1(p", "))}
CROSSREFS
Sequence in context: A206176 A205430 A208455 * A204802 A227931 A254195
KEYWORD
nonn
AUTHOR
M. F. Hasler, Feb 28 2012
EXTENSIONS
a(20) and a(21) added by Robert C. Lyons, Nov 16 2024.
STATUS
approved