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%I #21 Dec 05 2019 17:25:47
%S 986,1240,1928,4054,14252,47528,101728
%N Numbers k such that 10^k - 987654321 is prime.
%C Note that 987654321 is the largest pandigital number in base-10, omitting 0.
%t Select[Range[10000], PrimeQ[10^# - 987654321] &] (* _Robert Price_, Dec 05 2019 *)
%o (PARI) for(n=1,10^4,if(ispseudoprime(10^n-987654321),print1(n,", ")))
%Y Cf. A248349, A248350, A248351, A050289.
%K nonn,hard,more
%O 1,1
%A _Derek Orr_, Oct 05 2014
%E a(6)-a(7) from _Robert Price_, Dec 05 2019
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