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.

A167620 Numbers that are multiples of their digital product, where this digital product also appears as their least significant digits.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 15, 111, 112, 115, 315, 612, 1111, 1112, 1113, 1115, 1116, 11111, 11112, 11115, 12312, 13212, 21312, 23112, 31212, 32112, 111111, 111112, 111115, 111315, 111612, 113115, 116112, 131115, 161112, 311115, 511175
Offset: 1

Views

Author

Claudio Meller, Nov 07 2009

Keywords

Comments

Subsequence of A007602. - R. J. Mathar, Nov 12 2009
The digital products of the terms are a subsequence of A238985. - Karl-Heinz Hofmann, Feb 16 2024

Examples

			612 is in the list because 6*1*2=12, 612 is a multiple of 12, and 12 is the final two digits of 612.
		

Crossrefs

Programs

  • PARI
    is(n) = { my(vp = vecprod(digits(n))); vp != 0 && n %vp == 0 && n % 10^(#digits(vp)) == vp } \\ David A. Corneth, Mar 30 2021
    
  • Python
    A167620 = []
    for k in range(1,511176):
        dprod, k_str = 1, str(k)
        for d in range(0,len(k_str)): dprod *= int(k_str[d])
        if dprod != 0 and k % dprod == 0 and str(dprod) == k_str[-(len(str(dprod))):]:
            A167620.append(k)
    print(A167620) # Karl-Heinz Hofmann, Jan 26 2024