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A038562
Let a (resp. b,c,d) be number of primes in the range {2..p} that end in 1 (resp. 3,7,9); sequence gives p such that a=d and b=c.
1
2, 7, 19, 37, 139, 151, 163, 173, 181, 199, 229, 397, 409, 421, 491, 557, 577, 593, 601, 613, 659, 809, 839, 857, 881, 887, 1439, 1459, 1657, 1667, 1889, 2029, 3023, 3863, 4283, 5261, 5297, 5437, 5479, 7853, 7873, 7901, 8263, 8291, 8297, 8353, 8521, 8597
OFFSET
2,1
EXAMPLE
E.g. n=19 {2,3,5,7,11,13,17,19}->{2,3,5,7,1,3,7,9}, a=1, b=2, c=2, d=1, b=c and a=d, therefore accept 19.
CROSSREFS
Cf. A038563.
Sequence in context: A152608 A334520 A308269 * A140610 A152461 A215208
KEYWORD
easy,nonn
AUTHOR
Author's name lost.
STATUS
approved