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A244344
Numbers such that the largest prime factor equals the sum of the 4th power of the other prime factors.
1
582, 1164, 1746, 2328, 3492, 4656, 5238, 6410, 6984, 9312, 10476, 12820, 13968, 15714, 18624, 20952, 25640, 27936, 31428, 32050, 33838, 37248, 41904, 47142, 51280, 55872, 56454, 62856, 64100, 67676, 74496, 83808, 94284, 102560, 111744, 112908, 125712, 128200
OFFSET
1,1
COMMENTS
Observation: it seems that the prime divisors of a majority of numbers n are of the form {2, p, q} with q = 2^4 + p^4, but there exists more rarely odd numbers with more prime divisors (example from Michel Marcus: 3955413 = 3*7*11*17123).
LINKS
EXAMPLE
582 is in the sequence because the prime divisors of 582 are 2, 3 and 97 => 2^4 + 3^4 = 97.
MATHEMATICA
fpdQ[n_]:=Module[{f=Transpose[FactorInteger[n]][[1]]}, Max[f]-Total[Most[f]^4]==0]; Union[Select[Range[2, 5*10^5], fpdQ]]
CROSSREFS
KEYWORD
nonn
AUTHOR
Michel Lagneau, Jun 26 2014
STATUS
approved