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A342830 Primes p such that A001414(p+q) is the square of a prime, where q is the next prime after p. 1
11, 73, 461, 659, 787, 977, 1171, 1181, 1571, 1873, 2039, 2267, 3229, 3823, 4159, 5527, 5563, 5651, 5813, 5857, 5881, 6793, 7877, 8117, 8573, 8719, 9133, 9887, 10463, 10867, 11731, 14087, 14533, 15497, 17401, 17881, 17957, 18839, 19181, 19207, 20719, 20981, 21139, 22051, 24979, 26003, 28537 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
EXAMPLE
a(3) = 461 is a term because it is prime, the next prime is 463, and A001414(461+463) = 25 = 5^2 where 5 is prime.
MAPLE
spf:= proc(n) local t; add(t[1]*t[2], t=ifactors(n)[2]) end proc:
filter:= proc(p) local t; t:= spf(p+nextprime(p));
issqr(t) and isprime(sqrt(t)) end proc:
select(filter, [seq(ithprime(i), i=1..1000)]);
CROSSREFS
Cf. A001414.
Sequence in context: A217946 A163775 A092244 * A155634 A335828 A003367
KEYWORD
nonn
AUTHOR
J. M. Bergot and Robert Israel, Mar 23 2021
STATUS
approved

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Last modified March 3 14:54 EST 2024. Contains 370512 sequences. (Running on oeis4.)