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 A089217 #14 Jan 26 2023 15:08:14 %S A089217 5,9,13,21,25,33,45,49,61,69,73,81,85,105,109,129,133,141,153,165,169, %T A089217 181,193,201,213,225,229,241,253,265,273,285,309,313,333,349,361,369, %U A089217 381,385,421,433,441,445,465,469,481,489,493,501,505,525,549,565,573 %N A089217 n-2 is a prime of the form 4*k+3. %D A089217 M. Cerasoli, F. Eugeni and M. Protasi, Elementi di Matematica Discreta, Bologna 1988. %D A089217 Emanuele Munarini and Norma Zagaglia Salvi, Matematica Discreta,UTET, CittaStudiEdizioni, Milano 1997. %F A089217 a(n) = A087915(n)+ A089193(n) %t A089217 Select[4*Range[0,200]+3,PrimeQ]+2 (* _Harvey P. Dale_, Jun 04 2017 *) %Y A089217 Cf. A087915, A089193. %K A089217 easy,nonn %O A089217 1,1 %A A089217 _Giovanni Teofilatto_, Dec 10 2003 %E A089217 Offset corrected by _Arkadiusz Wesolowski_, Aug 09 2011 %E A089217 Corrected and extended by _Harvey P. Dale_, Jun 04 2017