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%I #24 Jul 19 2022 01:33:42
%S 5,13,17,23,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97,101,103,107,
%T 109,113,127,131,137,139,149,151,157,163,167,173,179,181,191,193,197,
%U 199,211,223,227,229,233,239,241,251,257,263,269,271,277,281,283,293
%N Primes p such that 10^p - 9^p is composite.
%t Select[Prime[Range[100]],!PrimeQ[10^#-9^#]&] (* _Harvey P. Dale_, Jun 21 2012 *)
%o (PARI) apmb(a,b,n) = { forprime(x=2,n, y=a^x-b^x; if(!ispseudoprime(y), print1(x","); ) ) }
%Y Cf. A016189, A062576.
%Y Primes k such that x^k - (x-1)^k is composite: A087489 (x=3), A087490 (x=4), A087685 (x=5), A087749 (x=6), A087759 (x=7), A087763 (x=8), A087894 (x=9), this sequence (x=10).
%K nonn
%O 1,1
%A _Cino Hilliard_, Oct 26 2003
%E Offset corrected by _Mohammed Yaseen_, Jul 19 2022
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