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URL: https://oeis.org/A229549

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A229549
Numbers k such that k*(sum of digits of k) is a palindrome.
5
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
OFFSET
1,3
LINKS
EXAMPLE
829*(8+2+9) = 15751 (palindrome), so 829 is a term 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 *)
Select[Range[0, 10000], PalindromeQ[# Total[IntegerDigits[#]]]&] (* Harvey P. Dale, Jun 30 2025 *)
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
KEYWORD
nonn,base
AUTHOR
Derek Orr, Sep 26 2013
EXTENSIONS
More terms from Derek Orr, Apr 10 2015
STATUS
approved