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A037277
Replace n with concatenation of its divisors >1.
4
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
1,2
LINKS
MATHEMATICA
FromDigits[Flatten[IntegerDigits/@Rest[Divisors[#]]]]&/@Range[40] (* Harvey P. Dale, Nov 06 2011 *)
PROG
(Haskell)
a037277 1 = 0
a037277 n = read $ concat $ map show $ tail $ a027750_row n
-- Reinhard Zumkeller, May 01 2012, Feb 07 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
CROSSREFS
KEYWORD
nonn,easy,base,nice
EXTENSIONS
More terms from Erich Friedman
STATUS
approved