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 A062687 Numbers all of whose divisors are palindromic. 22
 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 22, 33, 44, 55, 66, 77, 88, 99, 101, 121, 131, 151, 181, 191, 202, 242, 262, 303, 313, 353, 363, 373, 383, 393, 404, 484, 505, 606, 626, 707, 727, 757, 787, 797, 808, 909, 919, 929, 939, 1111, 1331, 1441, 1661, 1991, 2222, 2662 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Amiram Eldar, Table of n, a(n) for n = 1..10000 (terms 1..221 from Indranil Ghosh) EXAMPLE The divisors of 44 are 1, 2, 4, 11, 22 and 44, which are all palindromes, so 44 is in the sequence. 808 has divisors are 1, 2, 4, 8, 101, 202, 404, 808, so 808 is in the sequence. 818 is palindromic, but since it's 2 * 409, it's not in the sequence. MAPLE isA062687 := proc(n)     for d in numtheory[divisors](n) do         if not isA002113(d) then             return false;         end if;     end do;     true ; end proc: # R. J. Mathar, Sep 09 2015 MATHEMATICA palQ[n_] := Module[{idn = IntegerDigits[n]}, idn == Reverse[idn]]; Select[Range[2750], And@@palQ/@Divisors[#] &] (* Harvey P. Dale, Feb 27 2012 *) PROG (PARI) isok(n) = {d = divisors(n); rd = vector(#d, i, subst(Polrev(digits(d[i])), x, 10)); (d == rd); } \\ Michel Marcus, Oct 10 2014 CROSSREFS Cf. A087991, A084325, A002385 (subset). Subsequence of A002113. Sequence in context: A110785 A193413 A087992 * A109882 A109872 A030285 Adjacent sequences:  A062684 A062685 A062686 * A062688 A062689 A062690 KEYWORD base,easy,nonn AUTHOR Erich Friedman, Jul 04 2001 STATUS approved

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Last modified December 7 04:21 EST 2021. Contains 349567 sequences. (Running on oeis4.)