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.

A350324 Missing even distances in full prime rulers, i.e., even numbers k, 0 < k < p-3 for some prime p, such that k is not the difference of two primes less than or equal to p.

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%I A350324 #14 Feb 10 2022 22:17:09
%S A350324 88,112,118,140,182,202,214,242,284,292,298,316,322,338,358,388,400,
%T A350324 410,422,448,470,478,490,512,526,532,548,578,622,632,664,682,692,700,
%U A350324 710,718,742,760,772,778,788,800,812,830,838,844,862,868,886,892,898,910,920,928,952,958,982,1000,1022,1040,1052,1072,1078,1108,1130,1136,1142,1154,1162,1172,1192,1204
%N A350324 Missing even distances in full prime rulers, i.e., even numbers k, 0 < k < p-3 for some prime p, such that k is not the difference of two primes less than or equal to p.
%C A350324 Inspired by the notion of 'distset' as in A349976, and the general idea of sets of natural numbers as marks of a 'ruler'.
%e A350324 a(1) = 88 < p - 3 for prime number p = 97, and there are no primes p1, p2 <= p with 88 = p1 - p2.
%p A350324 primedist := n -> {seq(2*j, j = 0..(ithprime(n) - 3)/2)} minus `union`(seq({seq(abs(ithprime(j) - ithprime(k)), k = 1..j)}, j = 1..n)):
%p A350324 `union`(seq(primedist(j), j = 1..200)); # _Peter Luschny_, Dec 24 2021
%o A350324 (PARI) genit(maxx=1300)={arr=List();forstep(x=2,maxx,2,q=nextprime(x+2);if(!isprime(q-x),listput(arr,x)));arr;} \\ _Bill McEachen_, Feb 09 2022
%Y A350324 Cf. A000230, A001223, A071904, A349976.
%K A350324 nonn
%O A350324 1,1
%A A350324 _Rainer Rosenthal_, Dec 24 2021