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A334416
Numbers m such that (m / sum of digits of m) is a palindrome.
4
1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 18, 21, 24, 27, 36, 42, 45, 48, 54, 63, 72, 81, 84, 110, 132, 198, 220, 264, 330, 396, 440, 550, 594, 605, 660, 715, 770, 792, 825, 880, 935, 990, 1010, 1056, 1188, 1212, 1310, 1386, 1452, 1584, 1782, 1810, 1812, 1815, 1818, 1848
OFFSET
1,2
COMMENTS
Not to be confused with A114440 whose first 23 terms are identical to the terms of this sequence, while A114440(24) = 108 and a(24) = 110.
EXAMPLE
The number 264 is a term of the sequence because it is divisible by the sum of its digits: 2+6+4=12; 264/12=22 and 22 is a palindrome.
MATHEMATICA
Select[Range[2000], PalindromeQ[# / Plus @@ IntegerDigits[#]] &] (* Amiram Eldar, Apr 28 2020 *)
PROG
(PARI) isok(m) = iferr(my(d=digits(m/sumdigits(m))); d==Vecrev(d), E, 0); \\ Michel Marcus, Apr 29 2020
CROSSREFS
Cf. A001101 (similar for primes).
Cf. A334417 (resulting palindromic quotients).
Subsequence of A005349 (Niven (or Harshad) numbers).
Subsequence: A276142 (palindromic terms).
Sequence in context: A356349 A343680 A114440 * A217973 A097518 A097569
KEYWORD
nonn,base
AUTHOR
Bernard Schott, Apr 28 2020
STATUS
approved