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A264744
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Exponent of the prime power A264734(n).
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1
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1, 1, 1, 2, 1, 2, 3, 1, 4, 1, 1, 1, 1
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OFFSET
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1,4
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COMMENTS
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LINKS
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EXAMPLE
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a(9) = 4 is the exponent of 81 = A264734(9) = 3^4.
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MATHEMATICA
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t = Prepend[Select[Range@ 100000, AllTrue[{# - 2, #, # + 2}, PrimePowerQ] &], 3]; Flatten@ Map[Last, FactorInteger@ # &@ t, {2}] (* Michael De Vlieger, Dec 03 2015, Version 10 *)
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PROG
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(PARI) is(k) = isprimepower(k) || k==1;
for(k=1, 1e6, if(is(k) && is(k+2) && is(k-2), print1(bigomega(k), ", "))) \\ Altug Alkan, Nov 23 2015
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CROSSREFS
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Cf. A025474, A264734 (prime power k such that both k - 2 and k + 2 is a prime power).
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KEYWORD
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nonn,more,less
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AUTHOR
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STATUS
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approved
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