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A108703 Numbers n such that a^s + b^s + c^s + ... is prime, where a*b*c* ... is the prime factorization of n and s is the digital sum of n. 0
10, 12, 22, 26, 40, 54, 99, 104, 117, 153, 178, 184, 210, 300, 350, 358, 368, 416, 424, 448, 464, 466, 500, 549, 603, 651, 810, 1020, 1100, 1116, 1143, 1190, 1380, 1528, 1629, 1726, 1816, 1860, 1926, 1952, 2001, 2097, 2220, 2400, 2439, 2523, 2536, 2613 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
959949 generates a prime with 227 digits: 3^45 + 3^45 + 106661^45.
LINKS
EXAMPLE
26 is in the sequence because 26 = 2*13 and 2^(2+6) + 13^(2+6) = 815730977, a prime.
MATHEMATICA
abcsQ[n_]:=PrimeQ[Total[Flatten[Table[#[[1]], {#[[2]]}]&/@FactorInteger[ n]]^Total[IntegerDigits[n]]]]; Select[Range[3000], abcsQ] (* Harvey P. Dale, Feb 15 2016 *)
CROSSREFS
Sequence in context: A061870 A348056 A120001 * A098785 A022324 A084953
KEYWORD
base,easy,nonn
AUTHOR
Jason Earls, Jun 20 2005
STATUS
approved

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Last modified May 9 07:04 EDT 2024. Contains 372346 sequences. (Running on oeis4.)