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 A276375 #17 Sep 10 2016 16:25:23 %S A276375 1,2,3,11,22,29,47,49,52,67,78,79,80,91,103,104,109,111,121,130,137, %T A276375 148,152,159,179,184,190,200,207,215,222,241,264,278,291,307,309,316, %U A276375 331,336,343,347,350,361,373,380,400,409,415,430,435,445,450,453,468 %N A276375 Numbers n such that A240024(n + 1) = A002808(n). %H A276375 Peter Kagey, <a href="/A276375/b276375.txt">Table of n, a(n) for n = 1..10000</a> %t A276375 c = Select[Range@ 600, CompositeQ]; a = {1, 4}; Do[k = 6; While[Or[PrimeQ@ k, MemberQ[a, k], CoprimeQ[a[[i - 1]], k]], k++]; AppendTo[a, k], {i, 3, Length@c + 1}]; Flatten@ Position[Union /@ Transpose@ {Rest@ a, c}, w_ /; Length@ w == 1] (* _Michael De Vlieger_, Sep 01 2016 *) %o A276375 (Haskell) %o A276375 a276375 n = a276375_list !! (n - 1) %o A276375 a276375_list = filter (\i -> a240024 (i + 1) == a002808 i) [1..] %Y A276375 Cf. A002808, A240024, A276374. %K A276375 nonn %O A276375 1,2 %A A276375 _Peter Kagey_, Aug 31 2016