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 A359123 #6 Dec 18 2022 21:06:29 %S A359123 1,1,2,3,6,6,3,3,3,6,6,3,4,8,12,18,3,6,18,6,9,12,18,15,3,3,12,9,15,6, %T A359123 18,6,9,6,18,6,15,9,12,3,3,15,18,12,9,6,18,6,3,18,12,12,9,6,3,3,9,3,3, %U A359123 7,17,9,51,6,9,6,12,21,21,3,6,27,27,30,6,27,9,21,12,36,84,6 %N A359123 First differences of A068811, halved. %H A359123 Michael De Vlieger, <a href="/A359123/b359123.txt">Table of n, a(n) for n = 1..10000</a> %t A359123 1/2*Differences@ Select[Prime@ Range[300], PrimeQ[10^(1 + Floor@ Log10[#]) - #] &] (* _Michael De Vlieger_, Dec 18 2022 *) %Y A359123 Cf. A068811, A359121, A359122. %K A359123 nonn %O A359123 1,3 %A A359123 _N. J. A. Sloane_, Dec 18 2022