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A248352
Numbers k such that 10^k - 987654321 is prime.
3
986, 1240, 1928, 4054, 14252, 47528, 101728
OFFSET
1,1
COMMENTS
Note that 987654321 is the largest pandigital number in base-10, omitting 0.
MATHEMATICA
Select[Range[10000], PrimeQ[10^# - 987654321] &] (* Robert Price, Dec 05 2019 *)
PROG
(PARI) for(n=1, 10^4, if(ispseudoprime(10^n-987654321), print1(n, ", ")))
CROSSREFS
KEYWORD
nonn,hard,more
AUTHOR
Derek Orr, Oct 05 2014
EXTENSIONS
a(6)-a(7) from Robert Price, Dec 05 2019
STATUS
approved