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A176558
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a(n) is the reverse concatenation of divisors of n.
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34
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1, 21, 31, 421, 51, 6321, 71, 8421, 931, 10521, 111, 1264321, 131, 14721, 15531, 168421, 171, 1896321, 191, 20105421, 21731, 221121, 231, 2412864321, 2551, 261321, 27931, 28147421, 291, 30151065321, 311, 32168421, 331131, 341721, 35751, 361812964321, 371
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OFFSET
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1,2
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COMMENTS
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LINKS
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EXAMPLE
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For n=12; divisors of 12: 1,2,3,4,6,12; a(12)=1264321 (reverse concatenation).
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MAPLE
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a:= n-> parse(cat(sort([numtheory[divisors](n)[]], `>`)[])):
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MATHEMATICA
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Table[FromDigits@ Flatten@ Map[IntegerDigits, Reverse@ Divisors@ n], {n, 34}] (* Michael De Vlieger, Jan 23 2017 *)
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PROG
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(PARI) a(n) = {s = ""; fordiv(n, d, s = concat(Str(d), s)); eval(s); } \\ Michel Marcus, Feb 16 2015
(Python)
from sympy import divisors
def a(n): return int("".join(str(d) for d in divisors(n)[::-1]))
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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