cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A348370 Numbers k such that pi(reversal(prime(k))) = reversal(k). Ignore leading 0's.

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%I A348370 #13 Dec 10 2023 14:28:56
%S A348370 1,2,3,4,5,12,21,86,235,8114118,535252535
%N A348370 Numbers k such that pi(reversal(prime(k))) = reversal(k). Ignore leading 0's.
%C A348370 535252535 is a term (not necessarily the next one), so it seems this sequence is a supersequence of A069469.
%C A348370 From _Martin Ehrenstein_, Nov 06 2021: (Start)
%C A348370 Equivalently: Numbers k such that prime(reversal(k)) <= reversal(prime(k)) < prime(reversal(k)+1). Ignore leading 0's.
%C A348370 Thus A069469 is indeed a subsequence.
%C A348370 a(12) > 10^10. (End)
%t A348370 Select[Range[300],PrimePi[IntegerReverse[Prime[#]]]==IntegerReverse[#]&]
%Y A348370 Cf. A000040, A000720, A004086, A069469.
%K A348370 nonn,base,more
%O A348370 1,2
%A A348370 _Ivan N. Ianakiev_, Oct 15 2021
%E A348370 a(11) verified by _Martin Ehrenstein_, Nov 06 2021