A166503 Numbers k with property that k^2 is the concatenation of two or more prime numbers.

5, 15, 17, 19, 23, 27, 49, 51, 53, 69, 73, 77, 85, 87, 107, 109, 115, 123, 141, 147, 151, 153, 157, 159, 163, 165, 171, 173, 177, 181, 187, 191, 199, 219, 229, 231, 233, 235, 239, 241, 243, 267, 269, 277, 279, 281, 289, 299, 319, 327, 331, 335, 337, 343, 357

Offset

1,1

Comments

Only odd numbers are eligible.

Links

Jinyuan Wang, Table of n, a(n) for n = 1..10000

Formula

a(n) = sqrt(A038692(n)).

Prog

(PARI) for(n=1, 9999, is_A152242(n^2) & print1(n, ", ")) \\ M. F. Hasler, Oct 15 2009

Crossrefs

Cf. A019549, A038692, A105184, A129800.

Sequence in context: A109161 A065908 A297124 * A231720 A134453 A370919

Adjacent sequences: A166500 A166501 A166502 * A166504 A166505 A166506

Keyword

nonn,base

Author

Zak Seidov, Oct 15 2009

Extensions

Terms updated according to stricter definition of A152242 by M. F. Hasler, Oct 15 2009

Status

approved