A290751 Primes p such that the concatenation 1p is a semiprime.

5, 11, 19, 23, 29, 41, 43, 59, 61, 83, 101, 137, 139, 149, 157, 167, 191, 199, 211, 227, 241, 257, 263, 271, 293, 313, 317, 337, 347, 349, 379, 383, 389, 397, 401, 457, 461, 509, 541, 563, 569, 577, 631, 641, 643, 661, 673, 691, 727, 739, 751, 757, 761, 769

Offset

1,1

Links

Alois P. Heinz, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A290752, A290753.

Sequence in context: A140515 A056996 A102184 * A320518 A084720 A032674

Adjacent sequences: A290748 A290749 A290750 * A290752 A290753 A290754

Keyword

nonn,base

Author

N. J. A. Sloane, Aug 17 2017, following a suggestion from J. M. Bergot.

Extensions

More terms from Alois P. Heinz, Aug 27 2017

Status

approved