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 A318896 #41 Jul 15 2023 14:02:28 %S A318896 7314,8294,8645,11570,13629,13845,15105,15554,16554,17390,17654,18290, %T A318896 19005,20405,20769,21489,22010,22154,23001,23114,23529,24530,24765, %U A318896 24870,24969,25346,26690,26894,26961,27434,27965,28105,29145,29210,29414,29469,29666,30414 %N A318896 Numbers k such that k and k+1 are the product of exactly four distinct primes. %C A318896 This sequence is different from A140078. For example, A140078(4) = 9009 = 3^2 * 7 * 11 * 13 is not a term. %H A318896 Seiichi Manyama, <a href="/A318896/b318896.txt">Table of n, a(n) for n = 1..10000</a> %e A318896 n | a(n) | a(n)+1 %e A318896 --+-------------------------+------------------------- %e A318896 1 | 7314 = 2 * 3 * 23 * 53 | 7315 = 5 * 7 * 11 * 19 %e A318896 2 | 8294 = 2 * 11 * 13 * 29 | 8295 = 3 * 5 * 7 * 79 %e A318896 3 | 8645 = 5 * 7 * 13 * 19 | 8646 = 2 * 3 * 11 * 131 %o A318896 (PARI) is(n) = omega(n)==4 && omega(n+1)==4 && bigomega(n)==4 && bigomega(n+1)==4 \\ _Felix Fröhlich_, Sep 05 2018 %o A318896 (PARI) is(n) = factor(n)[, 2]~ == [1, 1, 1, 1] && factor(n+1)[, 2]~ == [1, 1, 1, 1] \\ _David A. Corneth_, Sep 06 2018 %Y A318896 Subsequence of A140078. %Y A318896 Cf. A046386, A052215, A215217, A263990, A318964. %K A318896 nonn %O A318896 1,1 %A A318896 _Seiichi Manyama_, Sep 05 2018