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Concatenation of the rightmost digit of the n-th prime and the leftmost digit of the (n+1)th prime.
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%I #20 Dec 25 2023 20:47:38

%S 23,35,57,71,11,31,71,92,32,93,13,74,14,34,75,35,96,16,77,17,37,98,38,

%T 99,71,11,31,71,91,31,71,11,71,91,91,11,71,31,71,31,91,11,11,31,71,92,

%U 12,32,72,92,32,92,12,12,72,32,92,12,72,12,32,33,73,13,33,73,13,73,73

%N Concatenation of the rightmost digit of the n-th prime and the leftmost digit of the (n+1)th prime.

%C This is the comma transform of the primes (see A367360).

%H Alois P. Heinz, <a href="/A166499/b166499.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = 10 * A007652(n) + A077648(n+1). - _Alois P. Heinz_, Nov 23 2023

%p a:= n-> parse(cat(""||(ithprime(n))[-1],""||(ithprime(n+1))[1])):

%p seq(a(n), n=1..99); # _Alois P. Heinz_, Nov 22 2023

%t With[{nmax=100},Map[10Mod[#[[1]],10]+IntegerDigits[#[[2]]][[1]]&,Partition[Prime[Range[nmax+1]],2,1]]] (* _Paolo Xausa_, Nov 24 2023 *)

%Y Cf. A007652, A077648, A367360.

%K base,nonn

%O 1,1

%A _Zak Seidov_, Oct 15 2009