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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
OFFSET
1,1
COMMENTS
Subsequence of A146326 (length of period continued fraction of (1 + sqrt(n))/2).
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 *)
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