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A366080
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Numbers that give a perfect power when added to their reverse.
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1
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2, 4, 8, 29, 38, 47, 56, 65, 74, 83, 92, 110, 122, 143, 164, 198, 221, 242, 263, 297, 320, 341, 362, 396, 440, 461, 495, 560, 594, 693, 792, 891, 990, 1030, 1120, 1210, 1300, 10100, 10148, 10340, 10395, 10403, 10683, 10908, 10980, 11138, 11330, 11385, 11673
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OFFSET
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1,1
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LINKS
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EXAMPLE
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8 is a term because 8 + 8 = 16 = 2^4 or 4^2.
10340 is a term because 10340 + 04301 = 14641 is a perfect power 11^4.
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MAPLE
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filter:= proc(n) local L, i, x;
L:= convert(n, base, 10);
x:= add(10^(i-1)*L[-i], i=1..nops(L));
igcd(ifactors(n+x)[2][.., 2])>1;
end proc:
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PROG
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(PARI) isok(k) = ispower(k + fromdigits(Vecrev(digits(k)))); \\ Michel Marcus, Oct 24 2023
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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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