login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A073965 Number of strings of length n over Z_5 with trace 0 and subtrace 2. 7
0, 0, 6, 30, 150, 650, 3150, 15500, 78000, 390000, 1952500, 9762500, 48831250, 244156250, 1220781250, 6103593750, 30517656250, 152587500000, 762939062500, 3814695312500, 19073484375000, 95367421875000, 476837167968750, 2384185839843750, 11920929199218750 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Same as the number of strings of length n over Z_5 with trace 0 and subtrace 3.

Same as the number of strings of length n over GF(5) with trace 0 and subtrace 2.

Same as the number of strings of length n over GF(5) with trace 0 and subtrace 3.

Same as the number of strings of length n over GF(5) with trace 1 and subtrace 0.

Same as the number of strings of length n over GF(5) with trace 4 and subtrace 0.

LINKS

Table of n, a(n) for n=1..25.

Max Alekseyev, PARI/GP scripts for miscellaneous math problems

F. Ruskey, Strings over Z_5 with given trace and subtrace

F. Ruskey, Strings over GF(5) with given trace and subtrace

FORMULA

a(n; t, s) = a(n-1; t, s) + a(n-1; t+4, s+4t+1) + a(n-1; t+3, s+3t+4) + a(n-1; t+2, s+2t+4) + a(n-1; t+1, s+t+1).

Empirical g.f.: 2*x^3*(50*x^4-50*x^3+30*x^2-15*x+3) / ((5*x-1)*(5*x^2-1)*(25*x^4-25*x^3+15*x^2-5*x+1)). - Colin Barker, Apr 03 2015

CROSSREFS

Cf. A073963, A073964, A073966, A073967, A073968, A073969, A073970.

Sequence in context: A319377 A079738 A127741 * A214940 A002913 A157519

Adjacent sequences:  A073962 A073963 A073964 * A073966 A073967 A073968

KEYWORD

easy,nonn

AUTHOR

Frank Ruskey, Nate Kube, Aug 15 2002

EXTENSIONS

Terms a(11) onward from Max Alekseyev, Apr 09 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 | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified August 18 12:29 EDT 2022. Contains 356212 sequences. (Running on oeis4.)