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.

A248210 Zeroless numbers k (numbers in A052382) such that k - DigitProduct(k) contains the same distinct digits as k.

Original entry on oeis.org

293, 362, 436, 545, 554, 631, 653, 749, 763, 891, 958, 965, 1293, 1362, 1436, 1545, 1554, 1631, 1653, 1749, 1763, 1891, 1958, 1965, 2193, 2331, 2491, 2536, 2556, 2565, 2693, 2917, 2954, 2963, 3162, 3231, 3325, 3382, 3529, 3534, 3635, 3651, 4291, 4515, 4533, 4551, 4634, 4935, 4952, 4971
Offset: 1

Views

Author

Derek Orr, Oct 03 2014

Keywords

Comments

Numbers that contain zeros trivially have this property. - Tanya Khovanova, Jul 19 2021

Examples

			631 - 6*3*1 = 613 contains the same digits as 631. So 631 is a term of this sequence.
		

Crossrefs

Cf. A052382 (zeroless numbers), A007954 (digit product).
Cf. A247888 (similar, with n + digit product).

Programs

  • Mathematica
    Select[Range@5000,(d=IntegerDigits@#;FreeQ[d,0]&&Union@IntegerDigits[#-Times@@d]==Union@d)&] (* Giorgos Kalogeropoulos, Jul 20 2021 *)
  • PARI
    for(n=1, 10^4, d=digits(n); p=prod(i=1, #d, d[i]); if(p && vecsort(digits(n), , 8)==vecsort(digits(n-p), , 8), print1(n, ", ")))
    
  • Python
    from math import prod
    def ok(n):
        s = str(n)
        return '0' not in s and set(str(n-prod(int(d) for d in s))) == set(s)
    print(list(filter(ok, range(5000)))) # Michael S. Branicky, Jul 18 2021