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A059496
a(1) = 2; a(n+1) is obtained by and trying to change just one digit of a(n), starting with the least significant digit, until a new prime is reached. Take the lexicographically earliest sequence. Digits may be replaced by any nonzero digit.
3
2, 3, 5, 7, 17, 11, 13, 19, 29, 23, 43, 41, 47, 37, 31, 61, 67, 97, 197, 191, 193, 199, 139, 131, 137, 127, 157, 151, 181, 281, 283, 223, 227, 229, 239, 233, 263, 269, 569, 563, 523, 521, 541, 547, 557, 577, 571, 271, 277, 257, 251, 211, 241, 641, 643, 647, 617, 613, 619
OFFSET
1,1
COMMENTS
The sequence is finite with last term a(114) = 149, see link and b-file. - Reinhard Zumkeller, Jan 06 2014
LINKS
Reinhard Zumkeller, Proof of finiteness
PROG
(Haskell)
a059496 n = a059496_list !! (n-1)
a059496_list = 2 : f [2] [2] where
f qs xs = g candidates where
g [] = []
g (ys:yss) | a010051 q == 0 || q `elem` qs = g yss
| otherwise = q : f (q:qs) ys
where q = foldr (\d r -> 10 * r + d) 0 ys
candidates = [us ++ [z] ++ vs | i <- [0 .. length xs - 1],
let (us, (_:vs)) = splitAt i xs, z <- [1..9]] ++
[xs ++ [z] | z <- [1..9]]
-- Reinhard Zumkeller, Jan 06 2014
CROSSREFS
Another decimal analog of A059458. See A059497 for primes that are missed. Cf. A059471, A059498.
Cf. A010051.
Sequence in context: A295266 A372407 A059471 * A066814 A358047 A072885
KEYWORD
nonn,base,nice,fini,full
AUTHOR
David W. Wilson, Feb 05 2001
STATUS
approved