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 A105338 #7 Apr 18 2025 14:41:48 %S A105338 0,1,3,6,10,15,21,28,36,45,55,66,78,91,105,120,136,153,171,190,210, %T A105338 231,253,276,300,325,351,378,406,435,465,496,16,49,83,118,154,191,229, %U A105338 268,308,349,391,434,478,11,57,104,152,201,251,302,354,407,461,4,60,117,175,234 %N A105338 a(n) = n*(n+1)/2 mod 512. %C A105338 Periodic with period length 1024. - _Ray Chandler_, Apr 18 2025 %H A105338 <a href="/index/Rec#order_1023">Index entries for linear recurrences with constant coefficients</a>, order 1023. %t A105338 Mod[#,512]&/@Accumulate[Range[0,60]] (* _Harvey P. Dale_, Dec 01 2018 *) %Y A105338 See A105198 for further information. %K A105338 nonn %O A105338 0,3 %A A105338 _Oscar Takeshita_, May 01 2005