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.
%I A094660 #22 Aug 25 2025 13:56:52
%S A094660 0,1,2,4,6,9,12,18,24,34,44,58,72,100,128,169,210,267,324,429,534,694,
%T A094660 854,1064,1274,1657,2040,2571,3102,3780,4458,5801,7144,9067,10990,
%U A094660 13472,15954,20356,24758,30607,36456,44280,52104,66168,80232,98524,116816,140797,164778
%N A094660 Number of permissible patterns of primes in a fixed interval of n consecutive integers.
%C A094660 Similar to A023192. (Here we ignore the empty pattern and start at 0.) These are called "admissible constellations" of primes. - _Don Reble_, Jun 12 2004
%H A094660 Similar work at <a href="http://www.opertech.com/primes/k-tuples.html">Permissible Patterns</a>.
%F A094660 a(n) = Sum_{k=1..floor((n+1)/2)} (n + 2 - 2*k)*A023189(k). - _Jon E. Schoenfield_, May 17 2024
%e A094660 a(5)=9 because primes can exist in interval as x.... .x... ..x.. ...x. ....x x.x.. .x.x. ..x.x or x...x
%Y A094660 Cf. A008407, A020497, A023189. Equals A023192 - 1.
%K A094660 nonn,changed
%O A094660 0,3
%A A094660 Thomas J Engelsma (tom(AT)opertech.com), Jun 09 2004
%E A094660 a(42)-a(48) from _Pontus von Brömssen_, Aug 25 2025