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.

A101701 Numbers n such that n = sum of the reversals of divisors of n.

Original entry on oeis.org

1, 207321, 890827, 7591023, 18368601, 4885292403
Offset: 1

Views

Author

Farideh Firoozbakht, Dec 23 2004

Keywords

Comments

a(7) > 10^11. - Donovan Johnson, Dec 27 2013

Examples

			18368601 is in the sequence because divisors of 18368601 are 1, 3, 6122867, 18368601 and 18368601 = 1 + 3 + 7682216 + 10686381.
		

Crossrefs

Programs

  • Mathematica
    Do[h = Divisors[n]; l = Length[h]; If[n == Sum[ FromDigits[Reverse[IntegerDigits[h[[k]]]]], {k, l}], Print[n]], {n, 370000000}]
  • Python
    from sympy import divisors
    A101701_list = [n for n in range(1,10**6) if n == sum([int(d) for d in (str(x)[::-1] for x in divisors(n))])]
    # Chai Wah Wu, Dec 06 2014

Extensions

a(6) from Donovan Johnson, Dec 07 2008