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A229549 Numbers n such that n*(sum of digits of n) is a palindrome. 4
0, 1, 2, 3, 11, 22, 42, 53, 56, 101, 111, 113, 121, 124, 182, 187, 202, 272, 353, 434, 515, 572, 616, 683, 739, 829, 888, 1001, 1111, 1357, 1507, 1508, 1624, 1717, 2002, 2074, 2852, 3049, 3146, 3185, 3326, 3342, 3687, 3747, 4058, 4066, 4391, 4719, 4724, 5038, 7579, 8569, 9391, 9471 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..54.

EXAMPLE

829*(8+2+9) = 15751 (palindrome). So, 829 is a member of this sequence.

MATHEMATICA

palQ[n_] := Block[{d = IntegerDigits@ n}, d == Reverse@ d]; Select[Range@ 10000, palQ[# Plus @@ IntegerDigits@ #] &] (* Michael De Vlieger, Apr 12 2015 *)

PROG

(Python)

def ispal(n):

..r = ''

..for i in str(n):

....r = i + r

..return n == int(r)

def DS(n):

..s = 0

..for i in str(n):

....s += int(i)

..return s

{print(n, end=', ') for n in range(10**4) if ispal(n*DS(n))}

## Simplified by Derek Orr, Apr 10 2015

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

for(n=0, 10^4, s=sumdigits(n); if(ispal(n*s), print1(n, ", "))) \\ Derek Orr, Apr 10 2015

CROSSREFS

Cf. A057147.

Sequence in context: A276375 A128921 A118595 * A229804 A241096 A057135

Adjacent sequences:  A229546 A229547 A229548 * A229550 A229551 A229552

KEYWORD

nonn,base

AUTHOR

Derek Orr, Sep 26 2013

EXTENSIONS

More terms from Derek Orr, Apr 10 2015

STATUS

approved

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Last modified September 25 15:27 EDT 2021. Contains 347658 sequences. (Running on oeis4.)