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.

A293728 Numbers k such that c(k,0) > c(k,1), where c(k,d) = number of d's in the first k digits of base-2 expansion of sqrt(2).

Original entry on oeis.org

11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 25, 26, 27, 29, 30, 31, 335, 609, 610, 611, 612, 613, 614, 615, 616, 617, 618, 619, 620, 621, 623, 624, 625, 626, 627, 628, 629, 630, 631, 632, 633, 634, 635, 675, 677, 683, 684, 685, 686, 687, 688, 689, 690
Offset: 1

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Author

Clark Kimberling, Oct 18 2017

Keywords

Comments

This sequence together with A293725 and A293727 partition the nonnegative integers.

Crossrefs

Programs

  • Mathematica
    z = 300; u = N[Sqrt[2], z]; d = RealDigits[u, 2][[1]];
    t[n_] := Take[d, n]; c[0, n_] := Count[t[n], 0]; c[1, n_] := Count[t[n], 1];
    Table[{n, c[0, n], c[1, n]}, {n, 1, 100}]
    u = Select[Range[z], c[0, #] == c[1, #] &]  (* A293725 *)
    u/2  (* A293726 *)
    Select[Range[z], c[0, #] < c[1, #] &]  (* A293727 *)
    Select[Range[z], c[0, #] > c[1, #] &]  (* A293728 *)