|
| |
|
|
A136699
|
|
Final nonzero digit of n! in base 13.
|
|
15
|
|
|
|
1, 1, 2, 6, 11, 3, 5, 9, 7, 11, 6, 1, 12, 12, 12, 11, 7, 2, 10, 8, 4, 6, 2, 7, 12, 1, 2, 2, 4, 12, 9, 6, 10, 5, 1, 9, 12, 2, 11, 7, 7, 1, 3, 12, 8, 9, 11, 10, 12, 3, 7, 6, 11, 11, 9, 1, 4, 7, 3, 8, 12, 4, 1, 11, 2, 10, 10, 7, 8, 6, 4, 11, 12, 5, 6, 8, 10, 3, 5, 5, 10, 4, 3, 2, 12, 6, 9, 3, 4, 5, 8, 4
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
0,3
|
|
|
LINKS
|
|
|
|
EXAMPLE
|
6! = 720 decimal = 435 tridecimal, so a(6) = 5.
|
|
|
MATHEMATICA
|
f[s_List] := Block[{a = s[[ -1]], len = Length@s}, Append[s, If[Mod[len, 13] == 0, Mod[a*len/13, 13], Mod[a*len, 13]]]]; Nest[f, {1}, 100] (* Robert G. Wilson v, May 03 2009 *)
f[n_] := Block[{id = IntegerDigits[n!, 13]}, While[id[[ -1]] == 0, id = Most@id]; id[[ -1]]]; Table[ f@n, {n, 0, 100}] (* Robert G. Wilson v, May 03 2009 *)
|
|
|
CROSSREFS
|
Cf. A000142, A136690, A136691, A136692, A136693, A136694, A136695, A136696, A008904, A136697, A136698, A136700, A136701, A136702.
|
|
|
KEYWORD
|
base,easy,nonn
|
|
|
AUTHOR
|
|
|
|
STATUS
|
approved
|
| |
|
|
