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.

A110949 Integers n such that 4*10^n + 61 is prime.

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%I A110949 #18 Jan 17 2019 13:44:08
%S A110949 1,2,7,11,191,248,1067,2666,5252,13400,22886,23739,29095
%N A110949 Integers n such that 4*10^n + 61 is prime.
%C A110949 See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "40061".
%C A110949 a(14) > 10^5. - _Robert Price_, Jan 22 2017
%H A110949 Makoto Kamada, <a href="https://stdkmd.net/nrr/prime/">List of near-repdigit-related prime numbers</a>.
%H A110949 <a href="/index/Pri#Pri_rep">Index entries for primes involving repunits</a>.
%e A110949 n = 7 is in the sequence because 4*10^7 + 61 = 4*10000000 + 61 = 40000000 + 61 = 40000061, which is prime.
%o A110949 (PARI) isok(n) = isprime(4*10^n+61); \\ _Michel Marcus_, Jan 22 2017
%Y A110949 Cf. A049054, A088274, A088275, A095688, A107083, A108049, A108050, A108052, A108054.
%K A110949 more,nonn
%O A110949 1,2
%A A110949 Julien Peter Benney (jpbenney(AT)ftml.net), Oct 04 2005
%E A110949 a(9)-a(11) from _Ray Chandler_, Dec 23 2010
%E A110949 Prepended a(1)=1 by _Robert Price_, Jan 22 2017
%E A110949 a(12)-a(13) from _Robert Price_, Jan 22 2017