A090096 Least n-pseudoprime which is a power of a prime number; smallest prime-power pseudoprime to base n.

4, 1194649, 121, 1194649, 4, 4377277921, 25, 9, 4, 9, 5041, 7252249, 4, 841, 848615161, 1194649, 4, 25, 9, 78961, 4, 169, 169, 25, 4, 9, 121, 9, 4, 49, 49, 25, 4, 2129445719544546771481, 9, 4377277921, 4, 289, 64625521, 121, 4, 529, 25, 9, 4, 9

Offset

1,1

Links

Table of n, a(n) for n=1..46.

Index entries for sequences related to pseudoprimes

Formula

a(n) = A039951(n)^2.

Example

n=2: -1+2^(1092*1094) = K*1093*1093 = K*1194649;
n=4k+1: a(4k+1)=4; for a(k)=9 see A090097; a(k)=25 see A090098.
Some large values after a(46): a(52)=219521; a(56)=418609; a(58)=17161; a(59)=7711729; a(83)=23726641; a(84)=26569; a(86)=4656561121; a(87)=3996001; a(92)=528529; a(95)=4566769; a(96)=11881.
Hard bases below 100 are 47, 66, 72, 88, 90.

Mathematica

t=list-of-true-p-powers-generated-independently lf[x_] := Length[FactorInteger[x]] base=6; Do[s=Mod[ -1+base^(Part[t, n]-1), Part[t, n]]; If[Equal[s, 0], Print[Part[t, n]]], {n, 1, Length[t]}]

Crossrefs

Cf. A007535, A090086, A247072, A039951.

Sequence in context: A079286 A275685 A124119 * A218484 A046362 A144122

Adjacent sequences: A090093 A090094 A090095 * A090097 A090098 A090099

Keyword

nonn,more

Author

Labos Elemer, Dec 01 2003

Extensions

More terms from Michel Marcus, Aug 30 2019

Status

approved