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!)
 A193292 Number of odd divisors of Fibonacci(n). 3
 1, 1, 1, 2, 2, 1, 2, 4, 2, 4, 2, 3, 2, 4, 4, 8, 2, 4, 4, 16, 4, 4, 2, 12, 6, 4, 8, 16, 2, 16, 4, 16, 4, 4, 8, 32, 8, 8, 4, 64, 4, 16, 2, 32, 16, 8, 2, 48, 8, 48, 4, 16, 4, 32, 16, 96, 16, 8, 4, 192, 4, 8, 16, 64, 8, 16, 8, 32, 16, 128, 4, 256, 4, 16, 24, 32 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 LINKS Charles R Greathouse IV, Table of n, a(n) for n = 1..1000 FORMULA a(n) = A001227(A000045(n)). - Michel Marcus, Jan 14 2014 EXAMPLE a(16) = 8 because Fibonacci(16) = 987 = 3 * 7 * 47 and the 8 odd divisors are {1, 3, 7, 21, 47, 141, 329, 987}. MATHEMATICA f[n_] := Block[{d = Divisors[Fibonacci[n]]}, Count[OddQ[d], True]]; Table[   f[n], {n, 110}] PROG (PARI) a(n)=n=fibonacci(n); numdiv(n>>valuation(n, 2)) \\ Charles R Greathouse IV, Jul 30 2011 CROSSREFS Cf. A000045, A193291. Sequence in context: A295878 A294931 A336856 * A275297 A300667 A129687 Adjacent sequences:  A193289 A193290 A193291 * A193293 A193294 A193295 KEYWORD nonn AUTHOR Michel Lagneau, Jul 21 2011 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 September 20 18:12 EDT 2020. Contains 337265 sequences. (Running on oeis4.)