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A103195 Concatenations of pairs of primes that differ by four. 8
37, 711, 1317, 1923, 3741, 4347, 6771, 7983, 97101, 103107, 109113, 127131, 163167, 193197, 223227, 229233, 277281, 307311, 313317, 349353, 379383, 397401, 439443, 457461, 463467, 487491, 499503, 613617, 643647, 673677, 739743, 757761, 769773 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..33.

Chris Caldwell, The First 1,000 Primes.

Eric Weisstein's World of Mathematics, Cousin Primes.

M. Wolf, On Twin and Cousin Primes.

FORMULA

a(n) = A023200(n) concatenated with A023200(n)+4. - Jonathan Vos Post, Mar 19 2005

EXAMPLE

The primes 3 and 7 differ by four, so the first term is 37.

MATHEMATICA

s = Select[ Prime[ Range[ 140]], PrimeQ[ # + 4] &]; FromDigits /@ Join @@@ IntegerDigits /@ Transpose[{s, s + 4}] (* Robert G. Wilson v, Mar 19 2005 *)

Join[{37}, FromDigits[Flatten[IntegerDigits/@#]]&/@Select[Partition[ Prime[ Range[ 200]], 2, 1], #[[2]]-#[[1]]==4&]] (* Harvey P. Dale, Sep 26 2016 *)

CROSSREFS

Sequence in context: A162165 A162389 A010989 * A282927 A220684 A225971

Adjacent sequences:  A103192 A103193 A103194 * A103196 A103197 A103198

KEYWORD

nonn,base

AUTHOR

Parthasarathy Nambi, Mar 18 2005

EXTENSIONS

More terms from Robert G. Wilson v, Mar 19 2005

STATUS

approved

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Last modified November 19 11:09 EST 2019. Contains 329319 sequences. (Running on oeis4.)