OFFSET
1,1
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
EXAMPLE
481 is here since spf(481) = 13 = 2^2+3^2, lpf(481)= 37 = 1^2+6^2 and sopfr(481)= 50 = 1^2+7^2.
MATHEMATICA
sumQ[n_] := AllTrue[FactorInteger[n], EvenQ[Last[#]] || Mod[First[#], 4]!=3 &]; aQ[n_] := CompositeQ[n] && AllTrue[{(f=FactorInteger[n])[[1, 1]], f[[-1, 1]], Plus @@ Times @@@ f}, sumQ]; Select[Range[574], aQ] (* Amiram Eldar, Dec 05 2019 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Jason Earls, Jun 15 2002
STATUS
approved