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A226778
Numbers having no common divisor > 1 with their reversal in decimal representation (see A043537).
4
1, 10, 13, 14, 16, 17, 19, 23, 25, 29, 31, 32, 34, 35, 37, 38, 41, 43, 47, 49, 52, 53, 56, 58, 59, 61, 65, 67, 71, 73, 74, 76, 79, 83, 85, 89, 91, 92, 94, 95, 97, 98, 100, 103, 104, 106, 107, 109, 112, 113, 115, 116, 118, 119, 122, 124, 125, 127, 128, 130
OFFSET
1,2
COMMENTS
A055483(a(n)) = 1.
LINKS
MATHEMATICA
Select[Range[130], GCD[#, FromDigits[Reverse[IntegerDigits[#]]]] == 1 &] (* Jayanta Basu, Jul 24 2013 *)
Select[Range[150], Intersection[Divisors[#], Divisors[IntegerReverse[#]]] == {1}&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jul 07 2020 *)
PROG
(Haskell)
a226778 n = a226778_list !! (n-1)
a226778_list = filter ((== 1) . a055483) [1..]
(PARI) isok(n) = gcd(n, subst(Pol(Vecrev(digits(n))), x, 10)) == 1; \\ Michel Marcus, Jul 02 2015
(PARI) is(n)=gcd(fromdigits(Vecrev(digits(n))), n)==1 \\ Charles R Greathouse IV, Aug 25 2016
CROSSREFS
Cf. A043537, A055483, A071249 (complement).
Sequence in context: A070837 A188643 A087140 * A061837 A256477 A247464
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Jun 18 2013
STATUS
approved