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A360277
Primes p that are congruent to 1 mod 2*k, where k = primepi(p) is the index of the prime.
0
11, 13, 1087, 64591, 64601, 64661, 3523969, 3524249, 189963073, 189963091, 189963847, 189968887, 189969319, 189969337, 1394194181, 1394194481, 1394194561, 1394197381, 1394199221, 1394199241, 10246935931, 10246936019, 10246936481, 75370121689, 75370121857, 75370122409
OFFSET
1,1
EXAMPLE
11 is a term since k = primepi(11) = 5 and 11 == 1 (mod 2*5).
13 is a term since k = primepi(13) = 6 and 13 == 1 (mod 2*6).
64661 is a term since k = primepi(64661) = 6466 and 64661 == 1 (mod 2*6466).
PROG
(PARI) lista(pmax) = {my(k = 0); forprime(p = 1, pmax, k+=2; if((p-1)%k==0, print1(p, ", "))); } \\ Amiram Eldar, Feb 01 2023
CROSSREFS
Subsequence of A048891.
Sequence in context: A111070 A110115 A073765 * A174831 A343838 A360388
KEYWORD
nonn
AUTHOR
Najeem Ziauddin, Feb 01 2023
EXTENSIONS
a(7)-a(8) from Michel Marcus, Feb 01 2023
a(9)-a(23) from Jon E. Schoenfield, Feb 01 2023
a(24)-a(26) from Amiram Eldar, Feb 01 2023
STATUS
approved