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

 

Logo

Thanks to everyone who made a donation during our annual appeal!
To see the list of donors, or make a donation, see the OEIS Foundation home page.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A047774 Number of dissectable polyhedra with symmetry of type C. 2
0, 0, 0, 0, 0, 0, 1, 1, 0, 5, 6, 0, 26, 32, 0, 133, 176, 0, 708, 952, 0, 3861, 5302, 0, 21604, 29960, 0, 123266, 172535, 0, 715221, 1007575, 0, 4206956, 5959656, 0, 25032840, 35622384, 0, 150413348, 214875099, 0, 911379384, 1306303424, 0, 5562367173 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,10

LINKS

Table of n, a(n) for n=1..46.

L. W. Beineke and R. E. Pippert, Enumerating dissectable polyhedra by their automorphism groups, Canad. J. Math., 26 (1974), 50-67.

FORMULA

Reference gives complicated recurrence.

MAPLE

# T=A001764

T := proc(n)

    if n < 0 then

        0;

    else

        (3*n)!/n!/(2*n+1)! ;

    end if;

end proc:

# U=A047749

U := proc(n)

    if type(n, 'integer') then

        if type(n, 'even') then

            T(n/2) ;

        else

            (3*n-1)/(n+1)*T((n-1)/2) ;

        end if;

    else

        0 ;

    end if;

end proc:

# V=A047750

V := proc(n)

    if type(n, 'integer') then

        if type(n, 'even') then

            2*U(n+1)-U(n) ;

        else

            2*U(n+1) ;

        end if;

    else

        0;

    end if;

end proc:

K := proc(n)

    if n < 1 then

        0 ;

    elif n = 1 then

        1;

    else

        U((n-5)/12) ;

    end if;

end proc:

J := proc(n)

    if type((n-5)/12, 'integer') then

        T((n-5)/12)-K(n) ;

        %/2 ;

    else

        0;

    end if ;

end proc:

Q := proc(n)

    if type((n-2)/6, 'integer') then

        U((n-2)/6) ;

    else

        0 ;

    end if;

end proc:

N := proc(n)

    if type((n-2)/6, 'integer') then

        T((n-2)/6)-Q(n) ;

        %/2 ;

    else

        0;

    end if ;

end proc:

DD := proc(n)

    2*U((n-1)/3)+V((n-2)/3)-2*K(n)-Q(n) ;

    %/2 ;

end proc:

OO := proc(n)

    if type((n-2)/6, 'integer') then

        T((n-2)/6)-Q(n) ;

        %/2 ;

    else

        0;

    end if ;

end proc:

C := proc(n)

    if n = 1 then

        0;

      elif modp(n, 3) = 1 then

        T((n-1)/3)-DD(n) ;

        %/2 ;

    else

        U((2*n-1)/3)-2*DD(n)-4*J(n) -2*K(n)-2*N(n)-2*OO(n)-Q(n) ;

        %/4 ;

    end if;

end proc:

seq(C(n), n=1..50) ; # R. J. Mathar, Jul 10 2013

CROSSREFS

Cf. A027610.

Sequence in context: A103492 A200010 A105580 * A243108 A287610 A298171

Adjacent sequences:  A047771 A047772 A047773 * A047775 A047776 A047777

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from R. J. Mathar, Jul 10 2013

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 January 21 10:26 EST 2020. Contains 331105 sequences. (Running on oeis4.)