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.

A342440 The longest length of consecutive primes which sums to prime = A342439(n) < 10^n.

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%I A342440 #25 Mar 14 2021 06:08:51
%S A342440 2,6,21,65,183,543,1587,4685,13935,41708,125479,379317,1150971,
%T A342440 3503790,10695879,32729271,100361001,308313167,948694965
%N A342440 The longest length of consecutive primes which sums to prime = A342439(n) < 10^n.
%C A342440 Inspired by the 50th problem of Project Euler (see link).
%C A342440 The corresponding largest primes obtained are in A342439.
%C A342440 Solutions and Python program are proposed in Dreamshire and archive.today links. - _Daniel Suteu_, Mar 12 2021
%H A342440 Archive.today, <a href="https://archive.is/cd2SI">trizen / experimental-projects</a>.
%H A342440 Dreamshire, <a href="https://blog.dreamshire.com/project-euler-50-solution/">Project Euler 50 Solution</a>.
%H A342440 Project Euler, <a href="https://projecteuler.net/problem=50">Problem 50: Consecutive prime sum</a>.
%e A342440 A342439(1) = 5 = 2+3, hence a(1) = 2 since there are 2 terms in this longest sum.
%e A342440 A342439(2) = 41 = 2 + 3 + 5 + 7 + 11 + 13 hence a(2) = 6 since there are 6 terms in this longest sum.
%Y A342440 Cf. A342439, A342443, A342444.
%K A342440 nonn,more
%O A342440 1,1
%A A342440 _Bernard Schott_, Mar 12 2021
%E A342440 a(4)-a(17) from _Daniel Suteu_, Mar 12 2021
%E A342440 a(18)-a(19) from _Martin Ehrenstein_, Mar 13 2021