cp's OEIS Frontend

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.

A184118 Upper s(n)-Wythoff sequence, where s(n) = 2n + 1.

Original entry on oeis.org

4, 7, 10, 14, 17, 21, 24, 28, 31, 34, 38, 41, 45, 48, 51, 55, 58, 62, 65, 68, 72, 75, 79, 82, 86, 89, 92, 96, 99, 103, 106, 109, 113, 116, 120, 123, 127, 130, 133, 137, 140, 144, 147, 150, 154, 157, 161, 164, 168, 171, 174, 178, 181, 185, 188, 191, 195, 198, 202, 205, 208, 212, 215, 219, 222, 226, 229, 232, 236, 239, 243, 246, 249, 253, 256, 260, 263, 267, 270, 273, 277, 280, 284, 287, 290, 294, 297, 301, 304, 307, 311, 314, 318, 321, 325, 328, 331, 335, 338, 342
Offset: 1

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Author

Clark Kimberling, Jan 09 2011

Keywords

Comments

See A184117 (the lower s(n)-Wythoff sequence).

Crossrefs

Programs

  • Magma
    [Floor((2+Sqrt(2))*n+Sqrt(2)/2): n in [1..100]]; // Vincenzo Librandi, Jan 07 2019
  • Maple
    a:=n->floor((2+sqrt(2))*n+sqrt(2)/2): seq(a(n),n=1..80); # Muniru A Asiru, Jan 08 2019
  • Mathematica
    k=2; r=-1;
    mex:=First[Complement[Range[1, Max[#1]+1], #1]]&;
    S[n_]:=k n-r; A[1]=1; B[n_]:=B[n]=S[n]+A[n];
    A[n_]:=A[n]=mex[Flatten[Table[{A[i], B[i]}, {i, 1, n-1}]]];
    Table[S[n], {n, 30}]
    Table[A[n], {n, 100}]
    Table[B[n], {n, 100}]
    Table[Floor[(2 + Sqrt[2]) n + Sqrt[2] / 2], {n, 80}] (* Vincenzo Librandi, Jan 07 2019 *)
  • PARI
    A184118_upto(N,s(n)=2*n+1,U=[0],b=[])={until(b[#b]>=N, b=concat(b,s(1+#b)+U[1]+=1); U=setunion(U,[b[#b]]); while(#U>1&&U[2]==U[1]+1,U=U[^1]));b} \\ M. F. Hasler, Jan 07 2019
    

Formula

a(n) = A184117(n) + s(n) for all n. - M. F. Hasler, Jan 07 2019