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A114016 Least n-digit prime which differs from the next prime at every corresponding digit. 1
2, 19, 199, 1999, 19997, 199999, 2999999, 19999999, 199999991, 1999999973, 19999999967, 299999999989, 1999999999981, 19999999999997, 399999999999997, 1999999999999943, 49999999999999993, 199999999999999949, 1999999999999999909, 19999999999999999939 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The corresponding next-primes are 3, 23, 211, 2003, 20011, 200003, 3000017, ... - Michel Marcus, Sep 15 2013

LINKS

Table of n, a(n) for n=1..20.

EXAMPLE

1999 is a term as the next prime 2003 differs at every corresponding position (1,2), (9,0),(9,0),(9,3).

PROG

(PARI) ok(fp) = {fpa = precprime(fp); fpb = nextprime(fp); da = digits(fpa); db = digits(fpb); for (i=1, #da, if (da[i] == db[i], return (0)); ); return (fpa); }

a(n) = {if (n == 1, return (2)); for (i = 2, 9, if (p = ok(i*10^(n-1)), return(p)); ); return (0); } \\ Michel Marcus, Sep 15 2013

CROSSREFS

Cf. A114017.

Sequence in context: A128970 A218117 A145104 * A268707 A037071 A126039

Adjacent sequences:  A114013 A114014 A114015 * A114017 A114018 A114019

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy, Nov 12 2005

EXTENSIONS

2 more terms from R. J. Mathar, Aug 31 2007

More terms from Michel Marcus, Sep 15 2013

STATUS

approved

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Last modified August 9 01:35 EDT 2020. Contains 336310 sequences. (Running on oeis4.)