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.

A114924 Primes p such that pi(p) is obtained by dropping one of the digits of p in decimal expansion.

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%I A114924 #5 Dec 29 2024 12:24:52
%S A114924 17,12491,14723,42437,57089,58193,61051,63131,63347,64553,64567,64577,
%T A114924 64591,64601,64661,64679,64951,65071,65173,65293,65881,66863,69931,
%U A114924 79817,99551,129083,165103,263071,284833,1407647,1515259,4303027
%N A114924 Primes p such that pi(p) is obtained by dropping one of the digits of p in decimal expansion.
%C A114924 If n>31 then we can get pi(a(n)) by dropping the first digit of a(n). Next term is greater than prime(20000000).
%e A114924 95517973 is in the sequence because 95517973 is prime and pi(95517973)=5517973.
%t A114924 Do[h=IntegerDigits[Prime@n]; l=Length[h]; If[MemberQ[Table[ FromDigits[Drop[h, {k}]], {k, l}], n], Print[Prime@n]], {n, 20000000}]
%t A114924 prpiQ[n_]:=MemberQ[FromDigits/@Table[Drop[IntegerDigits[n],{d}],{d,IntegerLength[n]}],PrimePi[n]]; Select[Prime[Range[310000]],prpiQ] (* _Harvey P. Dale_, Dec 29 2024 *)
%Y A114924 Cf. A114924.
%K A114924 fini,base,nonn
%O A114924 1,1
%A A114924 _Farideh Firoozbakht_, Jan 14 2006