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.
(See A192250.)
c[n_] := (2 n)!/(n! n!); (* central binomial coefficients, A000984 *) Table[c[n], {n, 0, 15}] q[x_] := x + 1; p[0, x_] := 1; p[n_, x_] := p[n - 1, x] + (x^n)*c[n] reductionRules = {x^y_?EvenQ -> q[x]^(y/2), x^y_?OddQ -> x q[x]^((y - 1)/2)}; t = Table[Last[Most[FixedPointList[Expand[#1 /. reductionRules] &, p[n, x]]]], {n, 0, 30}] Table[Coefficient[Part[t, n], x, 0], {n, 1, 30}] (* A192250 *) Table[Coefficient[Part[t, n], x, 1], {n, 1, 30}] (* A192251 *) Table[Coefficient[Part[t, n]/2, x, 1], {n, 1, 30}] (* A192070 *) (* by Peter J. C. Moses, Jun 20 2011 *)
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