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A072021
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Smallest solution to gcd(x, reverse(x)) = 5^n.
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5
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5, 5200, 521000, 5213750, 521875, 5218750, 52130234375, 5734841796875, 57869714843750, 526046650390625, 5265674365234375, 52187008544921875, 526515306396484375, 5213023309008789062500, 5213596736358642578125, 5260466086273193359375, 526041911745452880859375
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OFFSET
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1,1
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LINKS
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FORMULA
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EXAMPLE
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For n = 4, gcd(521875, 578125) = 3125 = 5^4.
For n = 8, a(8) = 5734841796875 = 5^9*2936239, reverse(a(8)) = 5786971484375 = 5^8*71*208657.
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PROG
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(PARI) a(n) = {my(k = 1); while (gcd(k, fromdigits(Vecrev(digits(k)))) != 5^n, k++); k; } \\ Michel Marcus, Jul 13 2018
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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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