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A135739
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Numbers n such that n+reverse(n) has only odd decimal digits (n not a multiple of 10).
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1
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12, 14, 16, 18, 21, 23, 25, 27, 32, 34, 36, 41, 43, 45, 52, 54, 61, 63, 72, 81, 209, 219, 229, 239, 249, 308, 318, 328, 338, 348, 407, 409, 417, 419, 427, 429, 437, 439, 447, 449, 506, 508, 516, 518, 526, 528, 536, 538, 546, 548, 605, 607, 609, 615, 617, 619
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OFFSET
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1,1
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COMMENTS
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Obviously n is in the sequence iff reverse(n) is in the sequence.
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LINKS
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EXAMPLE
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409 + 904 = 1313 has only odd digits, so 409 and 904 are in the sequence.
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MATHEMATICA
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odQ[n_]:=Module[{t=Count[IntegerDigits[n+FromDigits[Reverse[IntegerDigits[n]]]], _?EvenQ]}, t==0&&!Divisible[n, 10]]; Select[Range[700], odQ] (* Harvey P. Dale, Feb 20 2013 *)
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PROG
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(PARI) reverse(n, m)=n=[n]; while(n=divrem(n[1], 10), m=10*m+n[2]); m odd=Vec("13579"); for(i=1, 999, i%10&!setminus(Set(Vec(Str(i+reverse(i)))), odd)&print1(i", "))
(Python)
def ok(n): return n%10 and set(str(n + int(str(n)[::-1]))) <= set("13579")
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CROSSREFS
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KEYWORD
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base,easy,nonn
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AUTHOR
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STATUS
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approved
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