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.

A277592 Numbers k such that k/10^m == 5 mod 10, where 10^m is the greatest power of 10 that divides n.

Original entry on oeis.org

5, 15, 25, 35, 45, 50, 55, 65, 75, 85, 95, 105, 115, 125, 135, 145, 150, 155, 165, 175, 185, 195, 205, 215, 225, 235, 245, 250, 255, 265, 275, 285, 295, 305, 315, 325, 335, 345, 350, 355, 365, 375, 385, 395, 405, 415, 425, 435, 445, 450, 455, 465, 475, 485
Offset: 1

Views

Author

Clark Kimberling, Nov 05 2016

Keywords

Comments

Positions of 5 in A065881.
Numbers having 5 as rightmost nonzero digit in base 10. This is one sequence in a 10-way splitting of the positive integers; the other nine are indicated in the Mathematica program.
This sequence differs from A121025, which includes 540.

Crossrefs

Programs

  • Mathematica
    z = 460; a[b_] := Table[Mod[n/b^IntegerExponent[n, b], b], {n, 1, z}]
    p[b_, d_] := Flatten[Position[a[b], d]]
    p[10, 1] (* A277588 *)
    p[10, 2] (* A277589 *)
    p[10, 3] (* A277590 *)
    p[10, 4] (* A277591 *)
    p[10, 5] (* A277592 *)
    p[10, 6] (* A277593 *)
    p[10, 7] (* A277594 *)
    p[10, 8] (* A277595 *)
    p[10, 9] (* A277596 *)