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 A156194 #21 Mar 15 2024 02:23:10
%S A156194 1,2,7,1,7,2,1,1,4,2,4,1,1,2,7,1,7,2,1,1,4,2,4,1,1,2,7,1,7,2,1,1,4,2,
%T A156194 4,1,1,2,7,1,7,2,1,1,4,2,4,1,1,2,7,1,7,2,1,1,4,2,4,1,1,2,7,1,7,2,1,1,
%U A156194 4,2,4,1,1,2,7,1,7,2,1,1,4,2,4,1
%N A156194 Period 12: 1,2,7,1,7,2,1,1,4,2,4,1 repeated.
%C A156194 Also the decimal expansion of 42390704747/333333333333. - _R. J. Mathar_, Feb 23 2009
%H A156194 <a href="/index/Rec#order_12">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,0,0,0,0,0,0,0,0,0,1).
%F A156194 Palindromic properties: a(12k+i) = a(12k+6-i), i=0..3. a(12k+7+i) = a(12k+11-i), i=0..2, and similarly for successive differences.
%F A156194 a(n) = A156095(n) mod 9.
%F A156194 a(n) = A156094(n+6) mod 9.
%F A156194 a(4n) + a(4n+1) + a(4n+2) + a(4n+3) = A010850(n).
%F A156194 G.f.: (1+2*x+7*x^2+x^3+7*x^4+2*x^5+x^6+x^7+4*x^8+2*x^9+4*x^10+x^11)/((1-x)*(1+x+x^2)*(1+x)*(1-x+x^2)*(1+x^2)*(x^4-x^2+1)). - _R. J. Mathar_, Feb 23 2009
%t A156194 PadRight[{},144,{1,2,7,1,7,2,1,1,4,2,4,1}] (* _Harvey P. Dale_, Mar 06 2012 *)
%K A156194 nonn,easy,less
%O A156194 0,2
%A A156194 _Paul Curtz_, Feb 05 2009
%E A156194 Edited by _R. J. Mathar_, Feb 23 2009
%E A156194 More terms from _Jinyuan Wang_, Feb 26 2020