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A047791
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Numbers n such that n plus digit sum of n (A007953) equals a prime.
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27
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1, 10, 11, 13, 14, 16, 19, 32, 34, 35, 37, 52, 53, 56, 58, 59, 71, 73, 76, 91, 92, 94, 95, 97, 100, 101, 103, 104, 106, 122, 124, 127, 128, 142, 143, 146, 149, 160, 163, 166, 167, 181, 182, 184, 185, 215, 217, 218, 232, 233, 238, 250, 253, 256, 257, 271, 272
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,2
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LINKS
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FORMULA
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EXAMPLE
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Digit sum of 13 = 1 + 3 = 4 -> 13 + 4 = 17 is prime.
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MATHEMATICA
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Select[Range[272], PrimeQ[#+Total[IntegerDigits[#]]]&] (* Jayanta Basu, May 03 2013 *)
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PROG
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(Haskell)
a047791 n = a047791_list !! (n-1)
a047791_list = filter ((== 1) . a010051' . a062028) [1..]
(PARI) select( is(n)=isprime(n+sumdigits(n)), [1..300]) \\ M. F. Hasler, Nov 08 2018
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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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EXTENSIONS
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More terms from Larry Reeves (larryr(AT)acm.org), Nov 16 2000
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STATUS
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approved
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