cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A068655 Primes which are a concatenation of at least two consecutive primes.

Original entry on oeis.org

23, 2357, 3137, 5711, 8389, 111317, 151157, 157163, 167173, 171923, 199211, 233239, 251257, 257263, 263269, 271277, 313741, 331337, 353359, 373379, 414347, 433439, 467479, 509521, 523541, 541547, 601607, 653659, 661673, 677683, 727733
Offset: 1

Views

Author

Amarnath Murthy, Feb 28 2002

Keywords

Examples

			111317 is a term as it is a concatenation of 11, 13 and 17. 199211 is a term as a concatenation of 199 and 211.
		

Programs

  • Mathematica
    Module[{pr=Prime[Range[500]],c2,c3,c4},c2=Select[FromDigits/@ (Flatten[ IntegerDigits[ #],1]&/@Partition[pr,2,1]),PrimeQ];c3=Select[ FromDigits/@ (Flatten[IntegerDigits[#],1]&/@Partition[pr,3,1]),PrimeQ];c4= Select[ FromDigits/@(Flatten[IntegerDigits[#],1]&/@Partition[ pr,4,1]),PrimeQ]; Take[Union[Join[c2,c3,c4]],50]] (* Harvey P. Dale, Apr 20 2017 *)

Extensions

Edited by Larry Reeves (larryr(AT)acm.org), Oct 09 2003