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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

Giovanni Resta, Table of n, a(n) for n = 1..500

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))}

## Simplified by Derek Orr, Apr 10 2015

(PARI) ispal(n)=n=digits(n); n==Vecrev(n)

dprod(n)=n=digits(n); prod(i=1, #n, n[i])

is(n)=my(d=dprod(n)); d && ispal(d*n) \\ Charles R Greathouse IV, Apr 30 2014

CROSSREFS

Cf. A007954.

Sequence in context: A025105 A257979 A095984 * A172258 A306395 A135206

Adjacent sequences:  A229547 A229548 A229549 * A229551 A229552 A229553

KEYWORD

nonn,base

AUTHOR

Derek Orr, Sep 26 2013

STATUS

approved

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Last modified September 25 20:01 EDT 2021. Contains 347659 sequences. (Running on oeis4.)