The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A244065 Pseudoprimes to base 3 that are not squarefree. 8
 121, 3751, 4961, 7381, 11011, 29161, 32791, 142901, 228811, 239701, 341341, 551881, 566401, 595441, 671671, 784201, 856801, 1016521, 1237951, 1335961, 1433971, 1804231 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Must be divisible by the square of a Mirimanoff prime, A014127. - Charles R Greathouse IV, Jun 21 2014 LINKS Felix Fröhlich and Charles R Greathouse IV, Table of n, a(n) for n = 1..10000 (first 196 terms from Fröhlich) PROG (PARI) for(n=2, 10^9, if(!isprime(n) && Mod(3, n)^(n-1)==1 && !issquarefree(n), print1(n, ", "))) (PARI) list(lim)=my(M=[11, 1006003], v=List(), p2); for(i=1, #M, p2=M[i]^2; forstep(n=p2, lim, p2, if(Mod(3, n)^(n-1)==1, listput(v, n)))); Set(v) \\ Good for lim <= 9.4 * 10^29; Charles R Greathouse IV, Jun 21 2014 CROSSREFS Cf. A005935, A158358, A014127. Sequence in context: A206629 A014758 A069600 * A231649 A212802 A272775 Adjacent sequences:  A244062 A244063 A244064 * A244066 A244067 A244068 KEYWORD nonn AUTHOR Felix Fröhlich, Jun 19 2014 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified June 21 00:40 EDT 2021. Contains 345329 sequences. (Running on oeis4.)