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 A154531 Primes that are a concatenation of consecutive primes in two ways. 2
 199211, 211199, 233239, 239233, 257263, 263257, 353359, 359353, 523541, 541523, 653659, 659653, 971977, 977971, 19731979, 19791973, 23332339, 23392333, 32593271, 32713259, 36373643, 36433637, 37613767, 37673761, 42834289, 42894283, 49934999, 49994993 (list; graph; refs; listen; history; text; internal format)
 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 Cf. A133986, A154530. Sequence in context: A205638 A031687 A234034 * A043592 A126558 A339752 Adjacent sequences:  A154528 A154529 A154530 * A154532 A154533 A154534 KEYWORD nonn,base AUTHOR Pierre CAMI, Jan 11 2009 EXTENSIONS Corrected by Harvey P. Dale, Feb 20 2017 STATUS approved

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Last modified June 18 04:41 EDT 2021. Contains 345098 sequences. (Running on oeis4.)