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 A171577 #16 Jul 08 2025 06:09:14
%S A171577 0,1,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,
%T A171577 97,101,103,107,109,113,127,131,137,139,149,151,157,163,167,173,179,
%U A171577 181,191,193,197,199,211,223,227,229,233,239,241,251,257,263,269,271,277
%N A171577 0, 1 and primes > 3.
%C A171577 0 together with A140475. [_Arkadiusz Wesolowski_, Aug 26 2011]
%t A171577 Join[{0,1},Prime[Range[3,60]]] (* _Harvey P. Dale_, May 06 2018 *)
%o A171577 (PARI) a(n)=if(n>2,prime(n),n-1) \\ _Charles R Greathouse IV_, Aug 26 2011
%K A171577 nonn,easy,less
%O A171577 1,3
%A A171577 _Juri-Stepan Gerasimov_, Dec 12 2009, Dec 16 2009