|
|
A131081
|
|
Periodic sequence (8, 7, 4, 1, 0, 1, 4, 7).
|
|
5
|
|
|
8, 7, 4, 1, 0, 1, 4, 7, 8, 7, 4, 1, 0, 1, 4, 7, 8, 7, 4, 1, 0, 1, 4, 7, 8, 7, 4, 1, 0, 1, 4, 7, 8, 7, 4, 1, 0, 1, 4, 7, 8, 7, 4, 1, 0, 1, 4, 7, 8, 7, 4, 1, 0, 1, 4, 7, 8, 7, 4, 1, 0, 1, 4, 7, 8, 7, 4, 1, 0, 1, 4, 7, 8, 7, 4, 1, 0, 1, 4, 7, 8, 7, 4, 1, 0, 1, 4, 7, 8, 7, 4, 1, 0, 1, 4, 7, 8, 7, 4, 1, 0, 1, 4, 7, 8
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
Fourth column of triangular array T defined in A131074.
|
|
LINKS
|
|
|
FORMULA
|
a(1) = 8, a(2) = a(8) = 7, a(3) = a(7) = 4, a(4) = a(6) = 1, a(5) = 0; for n > 8, a(n) = a(n-8).
G.f.: (8-x-3*x^2-3*x^3+7*x^4)/((1-x)*(1+x^4)).
|
|
MATHEMATICA
|
PadRight[{}, 120, {8, 7, 4, 1, 0, 1, 4, 7}] Harvey P. Dale, May 20 2012
|
|
PROG
|
(PARI) {m=105; for(n=1, m, r=(n-1)%8; print1(if(r==0, 8, if(r==1||r==7, 7, if(r==2||r==6, 4, if(r==4, 0, 1)))), ", "))}
(Magma) m:=105; [ [8, 7, 4, 1, 0, 1, 4, 7][(n-1) mod 8 + 1]: n in [1..m] ];
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,easy,less
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|