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 A061482 #12 Aug 27 2025 09:14:48 %S A061482 1,2,3,11,127,16195,262286407,68794159432716139, %T A061482 4732636372053966959311918076028751, %U A061482 22397847030088134373054567592093233271179679420451463713205492138771 %N A061482 a(1) = 1, a(2) = 2, a(n) = sum of products of previous terms taking n-2 at a time. %C A061482 The next term (a(11)) has 135 digits. - _Harvey P. Dale_, Feb 29 2012 %e A061482 a(3) = a(1) + a(2) = 3. %e A061482 a(4) = a(1)*a(2) + a(2)*a(3) + a(3)*a(1) = 11. %e A061482 a(5) = 1*2*3 + 1*2*11 + 1*3*11 + 2*3*11 = 127. %Y A061482 Cf. A061902 (lengths of terms). %K A061482 nonn,easy,changed %O A061482 1,2 %A A061482 _Amarnath Murthy_, May 05 2001 %E A061482 More terms from _Asher Auel_, May 05 2001. The 11th term has 135 digits.