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A166499 Concatenation of the rightmost digit of the n-th prime and the leftmost digit of the (n+1)th prime.

%I A166499 #20 Dec 25 2023 20:47:38
%S A166499 23,35,57,71,11,31,71,92,32,93,13,74,14,34,75,35,96,16,77,17,37,98,38,
%T A166499 99,71,11,31,71,91,31,71,11,71,91,91,11,71,31,71,31,91,11,11,31,71,92,
%U A166499 12,32,72,92,32,92,12,12,72,32,92,12,72,12,32,33,73,13,33,73,13,73,73
%N A166499 Concatenation of the rightmost digit of the n-th prime and the leftmost digit of the (n+1)th prime.
%C A166499 This is the comma transform of the primes (see A367360).
%H A166499 Alois P. Heinz, <a href="/A166499/b166499.txt">Table of n, a(n) for n = 1..10000</a>
%F A166499 a(n) = 10 * A007652(n) + A077648(n+1). - _Alois P. Heinz_, Nov 23 2023
%p A166499 a:= n-> parse(cat(""||(ithprime(n))[-1],""||(ithprime(n+1))[1])):
%p A166499 seq(a(n), n=1..99);  # _Alois P. Heinz_, Nov 22 2023
%t A166499 With[{nmax=100},Map[10Mod[#[[1]],10]+IntegerDigits[#[[2]]][[1]]&,Partition[Prime[Range[nmax+1]],2,1]]] (* _Paolo Xausa_, Nov 24 2023 *)
%Y A166499 Cf. A007652, A077648, A367360.
%K A166499 base,nonn
%O A166499 1,1
%A A166499 _Zak Seidov_, Oct 15 2009