|
|
A229550
|
|
Numbers n with nonzero digits such that n*(product of digits of n) is a palindrome.
|
|
2
|
|
|
1, 2, 3, 11, 19, 22, 35, 37, 77, 111, 115, 116, 121, 131, 212, 464, 671, 731, 1111, 1221, 1229, 2112, 4136, 4147, 6346, 9832, 11111, 11151, 11161, 11211, 11311, 12121, 12477, 12692, 12734, 17951, 18619, 21112, 22622
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
LINKS
|
|
|
EXAMPLE
|
4136*(4*1*3*6) = 297792 (a palindrome). So, 4136 is a member of this sequence.
|
|
PROG
|
(Python)
def ispal(n):
..r = ''
..for i in str(n):
....r = i + r
..return n == int(r)
def DP(n):
..p = 1
..for i in str(n):
....p *= int(i)
..return p
{print(n, end=', ') for n in range(10**4) if DP(n) and ispal(n*DP(n))}
(PARI) ispal(n)=n=digits(n); n==Vecrev(n)
dprod(n)=n=digits(n); prod(i=1, #n, n[i])
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,base
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|