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A095958 Twin prime pairs concatenated in decimal representation. 8
35, 57, 1113, 1719, 2931, 4143, 5961, 7173, 101103, 107109, 137139, 149151, 179181, 191193, 197199, 227229, 239241, 269271, 281283, 311313, 347349, 419421, 431433, 461463, 521523, 569571, 599601, 617619, 641643, 659661 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(n) mod 3 = 0 for n>1, proof: A007953(a(n)) = 2*A007953(A001359(n)+1) and A007953(A001359(n)) mod 3 = 2 for n>1, therefore A007953(a(n)) mod 3 = 0.

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

EXAMPLE

29 = A001359(5), 29 + 2 = 31 = A006512(5): a(5) = 2931.

MATHEMATICA

concat[{a_, b_}]:=FromDigits[Flatten[IntegerDigits/@{a, b}]]; concat/@ Select[Partition[Prime[Range[150]], 2, 1], #[[2]]-#[[1]]==2&] (* Harvey P. Dale, Apr 20 2012 *)

PROG

(Haskell)

a095958 n = a095958_list !! (n-1)

a095958_list = f $ map show a077800_list :: [Integer] where

   f (t:t':ts) = read (t ++ t') : f ts

-- Reinhard Zumkeller, Apr 20 2012

(MAGMA) [Seqint( Intseq(NthPrime(n+1)) cat Intseq(NthPrime(n)) ): n in [1..150 ]| NthPrime(n+1)-NthPrime(n) eq 2 ]; // Marius A. Burtea, Mar 21 2019

CROSSREFS

Cf. A045533, A001359, A006512.

Cf. A077800, subsequence of A045533.

Sequence in context: A189554 A267738 A219806 * A244057 A219457 A026064

Adjacent sequences:  A095955 A095956 A095957 * A095959 A095960 A095961

KEYWORD

nonn,base

AUTHOR

Reinhard Zumkeller, Jul 14 2004

STATUS

approved

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Last modified August 8 05:50 EDT 2020. Contains 336290 sequences. (Running on oeis4.)