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A121969
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Numbers n such that if you subtract n-reversed from n you get a natural number with the same digits as n.
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3
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954, 1980, 2961, 3870, 5823, 7641, 9108, 19980, 29880, 29961, 32760, 38970, 39780, 49680, 49842, 54270, 58923, 59580, 60273, 60732, 69462, 69480, 69723, 70254, 73260, 76941, 79344, 79380, 89226, 89280, 89604, 90810, 91908, 96732, 99108
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OFFSET
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1,1
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REFERENCES
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David Wells, The Penguin Dictionary of Curious and Interesting Numbers (Rev. ed. 1997), p. 154 (entry for 1980).
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LINKS
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EXAMPLE
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954 - 459 = 495, 19980 - 8991 = 10989.
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MATHEMATICA
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srdQ[n_]:=Module[{idn=IntegerDigits[n], rn}, rn=FromDigits[Reverse[idn]]; n>rn&&Sort[IntegerDigits[n-rn]]==Sort[idn]]; Select[Range[100000], srdQ] (* Harvey P. Dale, Jun 21 2013 *)
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PROG
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(PARI) isok(n) = {my(d = digits(n)); diff = my(n - subst(Polrev(d), x, 10)); (diff > 0) && (vecsort(digits(diff)) == vecsort(d)); } \\ Michel Marcus, Sep 04 2015
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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STATUS
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approved
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