OFFSET
1,1
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..1000
José María Grau, Antonio M. Oller-Marcén, Manuel Rodríguez, and Daniel Sadornil, Fermat test with Gaussian base and Gaussian pseudoprimes, Czechoslovak Mathematical Journal, Vol. 65 (2015), pp. 969-982; arXiv preprint, arXiv:1401.4708 [math.NT], 2014.
MATHEMATICA
fa=FactorInteger; phi[p_, s_] := Which[Mod[p, 4] == 1, p^(s-1)*(p-1), Mod[p, 4]==3, p^(s-1)*(p+1), s==1, 2, True, 2^(s+1)]; phi[1]=1; phi[n_] := Product[phi[fa[n][[i, 1]], fa[n][[i, 2]]], {i, Length[fa[n]]}]; Select[Range[1000], IntegerQ[FU[#]/phi[#]] && PrimeQ[#] == False &]
CROSSREFS
KEYWORD
nonn
AUTHOR
José María Grau Ribas, Jan 16 2014
EXTENSIONS
a(29)-a(35) from Amiram Eldar, Nov 24 2023
STATUS
approved