A037277 Replace n with concatenation of its divisors >1.

0, 2, 3, 24, 5, 236, 7, 248, 39, 2510, 11, 234612, 13, 2714, 3515, 24816, 17, 236918, 19, 2451020, 3721, 21122, 23, 234681224, 525, 21326, 3927, 2471428, 29, 2356101530, 31, 2481632, 31133, 21734, 5735, 23469121836, 37, 21938, 31339

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn
• easy
• base
• nice

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A027750, A037284, A037278, A106708.

Programs

Haskell

a037277 1 = 0
a037277 n = read $ concat $ map show $ tail $ a027750_row n
-- Reinhard Zumkeller, May 01 2012, Feb 07 2011

Mathematica

FromDigits[Flatten[IntegerDigits/@Rest[Divisors[#]]]]&/@Range[40] (* Harvey P. Dale, Nov 06 2011 *)

Python

from sympy import divisors
def a(n):
  divisors_gt1 = divisors(n)[1:]
  if len(divisors_gt1) == 0: return 0
  else: return int("".join(str(d) for d in divisors_gt1))
print([a(n) for n in range(1, 40)]) # Michael S. Branicky, Dec 31 2020

Extensions

More terms from Erich Friedman