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 A112488 #9 Jan 22 2017 21:54:33 %S A112488 3,35,340,3304,33740,367884,4302216,53961336,724534272,10386470016, %T A112488 158507316864,2567670088320,44027031755520,796963357981440, %U A112488 15192135816261120,304269507433658880,6388907821376256000 %N A112488 Third column of triangle A112486 used for e.g.f.s of |Stirling1| = |A008275| diagonals. %H A112488 G. C. Greubel, <a href="/A112488/b112488.txt">Table of n, a(n) for n = 2..445</a> %F A112488 a(n) = A112486(n, 2), n>=2. a(0)=0=a(1). %F A112488 a(n) = (n+2)*a(n-1) + (n+1)*A001705(n-1), n>=2, a(1):=0. %e A112488 340 = a(4) = 6*35 + 5*26. %t A112488 A112486[n_, k_] := A112486[n, k] = Which[n < 0 || k < 0 || k > n, 0, n == 0, 1, True, (n + k)*A112486[n - 1, k] + (n + k - 1)*A112486[n - 1, k - 1]]; Table[A112486[n, 2], {n, 2, 50}] (* _G. C. Greubel_, Jan 21 2017 *) %K A112488 nonn,easy %O A112488 2,1 %A A112488 _Wolfdieter Lang_, Sep 12 2005