A153048 Numbers n with property that n^2 is a concatenation of two 3-digit primes.

319, 337, 357, 363, 371, 387, 409, 447, 591, 663, 681, 701, 801, 827, 893

Offset: 1

Author

Zak Seidov, Dec 17 2008

Keywords

• fini
• full
• nonn
• base

Comments

There are exactly 15 such numbers.

Examples

			Corresponding squares are: 101761, 113569, 127449, 131769, 137641, 149769, 167281, 199809, 349281, 439569, 463761, 491401, 641601, 683929, 797449.
		

Programs

Mathematica

c = 0; t = 1000; re = Sort[Reap[Do[If[PrimeQ[p], Do[If[PrimeQ[q], r = p*t + q; s = Sqrt[r]; If[s == Floor[s], c++; Sow[s]]], {q, 101, 999, 2}]], {p, 101, 999, 2}]][[2, 1]]]