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 A268146 #7 Mar 05 2016 13:52:53
%S A268146 543,765,131211,191817,313029,434241,616059,737271,103102101,
%T A268146 109108107,139138137,151150149,181180179,193192191,199198197,
%U A268146 229228227,241240239,271270269,283282281,313312311,349348347,421420419,433432431,463462461,523522521,571570569,601600599
%N A268146 Twin prime pairs concatenated to their average in decimal representation (the greater twin prepended, the lesser appended).
%C A268146 The greater prime of a twin prime pair is prepended and the lesser one is appended to their average (nonprime, interprime).
%C A268146 a(n) mod 3 = 0, (See A095958).
%e A268146 a(1)=543: the greater prime {5} of the first twin prime pair {3, 5} is prepended and the lesser prime {3} is appended to their average {4}.
%t A268146 UpToN[k_]:=FromDigits//@ StringJoin//@ ToString/@ {#+1, #, #-1} &/@ Select[ Table[ Prime[n]+1, {n, 2, PrimePi[k]}], PrimeQ[#+1] &]; UpToN[10000]
%Y A268146 Cf. A001097, A014574, A095958, A111875, A268145.
%K A268146 nonn,base,easy
%O A268146 1,1
%A A268146 _Mikk Heidemaa_, Jan 27 2016