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%I #15 Jul 13 2023 01:53:25
%S 2,3,5,7,11,13,17,19,23,29,31,37,41,47,53,59,61,71,73,79,89,97,101,
%T 107,109,127,149,151,163,179,181,191,193,199,239,241,251,257,269,271,
%U 359,383,401,431,433,449,479,487,499,541,577,599,601,641,647,719,751
%N Primes neighboring a 5-smooth number.
%C This is to A219528 as 3-smooth numbers A003586 are to 5-smooth numbers A051037.
%H Amiram Eldar, <a href="/A219669/b219669.txt">Table of n, a(n) for n = 1..10000</a>
%F Primes INTERSECTION {2^i 3^j 5^k +/-1 for i,j,k >= 0}.
%e a(1) = 2 = 2^0 * 3^0 * 5^0 + 1 = 2^0 * 3^1 * 5^0 - 1.
%t mx = 2^10; t5 = Select[Sort[Flatten[Table[2^i * 3^j * 5^k, {i, 0, Log[2, mx]}, {j, 0, Log[3, mx]}, {k, 0, Log[5, mx]}]]], # <= mx &]; Union[Select[t5 + 1, PrimeQ], Select[t5 - 1, PrimeQ]] (* _T. D. Noe_, Nov 25 2012 *)
%Y Cf. A000040, A051037, A219528.
%K nonn,easy
%O 1,1
%A _Jonathan Vos Post_, Nov 24 2012
%E Corrected by _T. D. Noe_, Nov 25 2012
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