OFFSET
1,1
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
EXAMPLE
233 and 239 consecutive primes, 233239 and 239233 are both primes.
MATHEMATICA
ccp2[{a_, b_}]:=Module[{c=a*10^IntegerLength[b]+b, d=b*10^IntegerLength[a]+ a}, If[ AllTrue[ {c, d}, PrimeQ], {c, d}, {}]]; ccp2/@Partition[Prime[ Range[ 1000]], 2, 1]//Flatten (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Feb 20 2017 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Pierre CAMI, Jan 11 2009
EXTENSIONS
Corrected by Harvey P. Dale, Feb 20 2017
STATUS
approved