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A068655 Primes which are a concatenation of at least two consecutive primes. 2
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..31.

EXAMPLE

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.

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 *)

CROSSREFS

Sequence in context: A220653 A281787 A132937 * A232362 A233226 A233446

Adjacent sequences:  A068652 A068653 A068654 * A068656 A068657 A068658

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy, Feb 28 2002

EXTENSIONS

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

STATUS

approved

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Last modified December 8 18:37 EST 2019. Contains 329865 sequences. (Running on oeis4.)