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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 (list; graph; refs; listen; history; text; internal format)
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

Amiram Eldar, Table of n, a(n) for n = 1..1500

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

Cf. A094479, A193411, A185077.

Sequence in context: A172883 A260541 A162705 * A059468 A350663 A122694

Adjacent sequences:  A244341 A244342 A244343 * A244345 A244346 A244347

KEYWORD

nonn

AUTHOR

Michel Lagneau, Jun 26 2014

STATUS

approved

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Last modified July 2 04:14 EDT 2022. Contains 354985 sequences. (Running on oeis4.)