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A071786
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In prime factorization of n replace each prime with its reversal (in decimal notation).
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12
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1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 31, 14, 15, 16, 71, 18, 91, 20, 21, 22, 32, 24, 25, 62, 27, 28, 92, 30, 13, 32, 33, 142, 35, 36, 73, 182, 93, 40, 14, 42, 34, 44, 45, 64, 74, 48, 49, 50, 213, 124, 35, 54, 55, 56, 273, 184, 95, 60, 16, 26, 63, 64, 155, 66, 76, 284, 96, 70, 17, 72
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OFFSET
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1,2
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COMMENTS
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Prime factors counted with multiplicity. - Harvey P. Dale, Jul 08 2017
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LINKS
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FORMULA
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completely multiplicative with a(p) = A004086(p), p prime.
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EXAMPLE
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a(143) = a(11*13) = a(11)*a(13) = 11*31 = 341.
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MAPLE
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read("transforms") ; A071786 := proc(n) local ifs, a, d ; ifs := ifactors(n)[2] ; a := 1 ; for d in ifs do a := a*digrev(op(1, d))^op(2, d) ; od: a ; end: # R. J. Mathar, Jun 16 2009
# second Maple program:
r:= n-> (s-> parse(cat(seq(s[-i], i=1..length(s)))))(""||n):
a:= n-> mul(r(i[1])^i[2], i=ifactors(n)[2]):
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MATHEMATICA
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Table[Times@@IntegerReverse/@Flatten[Table[#[[1]], #[[2]]]&/@ FactorInteger[ n]], {n, 80}] (* Harvey P. Dale, Jul 08 2017 *)
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PROG
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(Haskell)
a071786 = product . map a004086 . a027746_row
(Python3)
from sympy import factorint
from operator import mul
from functools import reduce
....return 1 if n==1 else reduce(mul, (int(str(p)[::-1])**e for p, e in factorint(n).items())) # Chai Wah Wu, Aug 14 2014
(PARI) rev(n)=fromdigits(Vecrev(digits(n)))
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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