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A173673 a(2k) = floor(F(k)/2), a(2k+1) = ceiling(F(k)/2), where F = A000045 is the Fibonacci sequence. 1
0, 0, 0, 1, 0, 1, 1, 1, 1, 2, 2, 3, 4, 4, 6, 7, 10, 11, 17, 17, 27, 28, 44, 45, 72, 72, 116, 117, 188, 189, 305, 305, 493, 494, 798, 799, 1292, 1292, 2090, 2091, 3382, 3383, 5473, 5473, 8855, 8856, 14328, 14329, 23184, 23184, 37512, 37513, 60696, 60697, 98209, 98209, 158905, 158906, 257114, 257115, 416020, 416020 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,10

COMMENTS

Original definition:  Paired sequence: {male,female} ={Floor[A000045(n)/2],A000045[n]-Floor[A000045(n)/2]}

Shows excess of females over males in Fibonacci sequences.

LINKS

Colin Barker, Table of n, a(n) for n = 0..1000

FORMULA

a(2k) = floor(Fibonacci(k)/2), a(2k+1) = ceiling(Fibonacci(k)/2) = Fibonacci(k)-a(2k).

Empirical g.f.: x^3*(1+x+x^2+2*x^3+x^4+x^5) / ((1+x)*(1-x+x^2)*(1+x+x^2)*(1-x^2-x^4)). - Colin Barker, Aug 02 2016

MATHEMATICA

Table[{Floor[Fibonacci[j]/

      2], Fibonacci[j] - Floor[Fibonacci[j]/2]}, {j, 0, 30}]

Flatten[%]

PROG

(PARI) a(n)=(fibonacci(n\2)+n%2)\2 \\ M. F. Hasler, Nov 24 2010

CROSSREFS

Cf. A000045.

Sequence in context: A228117 A286218 A094997 * A330715 A018125 A292420

Adjacent sequences:  A173670 A173671 A173672 * A173674 A173675 A173676

KEYWORD

nonn

AUTHOR

Roger L. Bagula and Gary W. Adamson, Nov 24 2010

STATUS

approved

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Last modified March 30 22:55 EDT 2020. Contains 333132 sequences. (Running on oeis4.)