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A355980
Indices of primes in A049685.
1
2, 3, 6, 9, 15, 21, 44, 50, 114
OFFSET
1,1
COMMENTS
Related to the search of solutions of the pair of congruences p^2 == -5 (mod q), q^2 == -5 (mod p).
Cosgrave and Dilcher list terms up to 25000, including probable primes.
LINKS
J. B. Cosgrave and K. Dilcher, Pairs of reciprocal quadratic congruences involving primes, Fib. Quart. 51 (2) (2013) 98, after Theorem 4.
FORMULA
A074281(n) = A049685(a(n)).
a(n) = (A074304(n)-1)/2.
CROSSREFS
KEYWORD
nonn,more
AUTHOR
R. J. Mathar, Jul 22 2022
STATUS
approved