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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A063509 Squarefree Lucas numbers. 2
2, 1, 3, 7, 11, 29, 47, 123, 199, 322, 521, 843, 2207, 3571, 9349, 15127, 39603, 64079, 103682, 167761, 271443, 1149851, 3010349, 4870847, 12752043, 20633239, 33385282, 54018521, 87403803, 228826127, 370248451, 969323029, 1568397607 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Harry J. Smith, Table of n, a(n) for n = 0..200

MATHEMATICA

Select[LucasL[Range[0, 50]], SquareFreeQ] (* Harvey P. Dale, Jan 20 2020 *)

PROG

(PARI) for(n=0, 30, x=fibonacci(n)+2*fibonacci(n-1); if(issquarefree(x), print(x)))

(PARI) { n=-1; g=1; f=0; for (m=0, 10^9, if (issquarefree(a=f + 2*g), write("b063509.txt", n++, " ", a); if (n==200, break)); h=g; g=f; f+=h ) } \\ Harry J. Smith, Aug 24 2009

CROSSREFS

Cf. A000032.

Sequence in context: A174254 A024404 A077173 * A137766 A294620 A010758

Adjacent sequences:  A063506 A063507 A063508 * A063510 A063511 A063512

KEYWORD

nonn

AUTHOR

Jason Earls, Aug 09 2001

EXTENSIONS

More terms from Dean Hickerson, Aug 22 2001

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.

License Agreements, Terms of Use, Privacy Policy. .

Last modified August 14 09:14 EDT 2020. Contains 336480 sequences. (Running on oeis4.)