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!)
 A146478 a(n) = length of period of continued fraction (1 + sqrt(prime(n)))/2. 1
 2, 2, 1, 4, 2, 1, 3, 6, 4, 1, 8, 3, 5, 10, 4, 1, 6, 3, 10, 8, 9, 4, 2, 7, 9, 3, 12, 6, 7, 7, 12, 6, 7, 18, 5, 20, 5, 18, 4, 1, 14, 5, 16, 15, 3, 20, 26, 4, 2, 1, 9, 12, 19, 14, 3, 12, 5, 24, 9, 15, 18, 1, 14, 16, 19, 3, 34, 21, 14, 9, 9, 4, 20, 7, 30, 8, 7, 5, 3, 27, 18, 13, 16, 23, 4, 2, 19, 23, 3 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Subsequence of A146326 (length of period continued fraction of (1 + sqrt(n))/2). LINKS Zak Seidov, Table of n, a(n) for n = 1..1000 MAPLE A146478 := proc(p) local c; c := numtheory[cfrac](1/2+sqrt(p)/2, 'periodic', 'quotients') ; nops(c[2]) ; end: for n from 1 to 100 do printf("%d, ", A146478(ithprime(n))) ; od: # R. J. Mathar, Nov 05 2008 MATHEMATICA Table[Length[ContinuedFraction[(1+Sqrt[Prime[n]])/2][[2]]], {n, 100}] (* Zak Seidov, Mar 22 2011 *) CROSSREFS Cf. A000290, A078370, A146326-A146345, A146348-A146360. Sequence in context: A051720 A022693 A174498 * A289500 A325276 A098804 Adjacent sequences:  A146475 A146476 A146477 * A146479 A146480 A146481 KEYWORD nonn AUTHOR Artur Jasinski, Oct 30 2008 EXTENSIONS a(59) changed from 7 to 9 by R. J. Mathar, Nov 05 2008 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 January 25 23:08 EST 2020. Contains 331270 sequences. (Running on oeis4.)