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A083984
If k is a number with exactly two distinct decimal digits, say a and b, neither of which is 0 (i.e., a member of A101594), define the self-complement of k, SC(k), to be the number obtained by replacing a with b and vice versa. E.g. SC(232233) = 323322. Sequence contains numbers n such that n and SC(n) are relatively prime.
2
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, 112, 113, 115, 116, 118, 119, 121, 122, 131, 133, 151, 155, 166, 181, 188, 191, 199, 211, 212, 221, 223, 227
OFFSET
1,1
EXAMPLE
25 is a member as 25 and 52 are relatively prime, but 24 is not a member as 24 and 42 are not coprime.
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, May 22 2003
EXTENSIONS
More terms from David Wasserman, Dec 07 2004
Offset corrected by Andrew Howroyd, Sep 29 2024
STATUS
approved