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A105975
Near-repdigit primes with 9 as repeated digit.
9
199, 499, 599, 919, 929, 991, 997, 1999, 2999, 4999, 8999, 9199, 9929, 9949, 49999, 59999, 79999, 94999, 98999, 99929, 99989, 99991, 199999, 599999, 799999, 989999, 991999, 999199, 999499, 999599, 999959, 999979, 2999999, 4999999, 9899999
OFFSET
1,1
LINKS
Brady Haran and Simon Pampena, Glitch Primes and Cyclops Numbers, Numberphile video (2015)
EXAMPLE
a(2)=499 is a term because all digits are equal to 9 except one.
MATHEMATICA
Sort[Select[Flatten[Table[FromDigits/@(Flatten[Permutations/@Table[ Join[{n}, PadRight[{}, i, 9]], {n, {1, 2, 4, 5, 7, 8}}], 1]), {i, 2, 6}]], PrimeQ]] (* Harvey P. Dale, May 07 2015 *)
CROSSREFS
Sequence in context: A227284 A140632 A142814 * A095995 A358898 A159657
KEYWORD
base,nonn
AUTHOR
Shyam Sunder Gupta, Apr 29 2005
STATUS
approved