The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A153048 Numbers n with property that n^2 is a concatenation of two 3-digit primes. 5
 319, 337, 357, 363, 371, 387, 409, 447, 591, 663, 681, 701, 801, 827, 893 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS There are exactly 15 such numbers. LINKS EXAMPLE Corresponding squares are: 101761, 113569, 127449, 131769, 137641, 149769, 167281, 199809, 349281, 439569, 463761, 491401, 641601, 683929, 797449. 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]]] CROSSREFS Sequence in context: A225579 A261281 A126838 * A053020 A250660 A252410 Adjacent sequences:  A153045 A153046 A153047 * A153049 A153050 A153051 KEYWORD fini,full,nonn,base AUTHOR Zak Seidov, Dec 17 2008 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified August 16 05:55 EDT 2022. Contains 356160 sequences. (Running on oeis4.)