|
|
A068158
|
|
a(n) = floor[ n!/(R(n))! ], where R(n) = Digit reversal of n (A004086).
|
|
0
|
|
|
1, 1, 1, 1, 1, 1, 1, 1, 1, 3628800, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1216451004088320000, 106661318400, 1, 0, 0, 0, 0, 0, 0, 0, 44208809968698509772718080000000, 1320509264105545113600000, 10178348544000, 1, 0, 0, 0, 0, 0, 0
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,10
|
|
COMMENTS
|
If n < R(n) then a(n) =0, n is a palindrome a(n) = 1 and for n > R(n) n!/(R(n)! = an integer.
|
|
LINKS
|
|
|
EXAMPLE
|
a(21) = 21! / 12! = 51090942171709440000/479001600 = 106661318400.
|
|
CROSSREFS
|
|
|
KEYWORD
|
base,easy,nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|