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A057954
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Number of prime factors of 7^n - 1 (counted with multiplicity).
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19
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2, 5, 4, 8, 3, 8, 4, 10, 7, 8, 4, 13, 3, 9, 7, 13, 4, 12, 4, 14, 7, 9, 5, 18, 5, 8, 12, 13, 5, 14, 5, 16, 9, 8, 7, 18, 5, 9, 8, 18, 5, 15, 4, 15, 12, 9, 4, 22, 8, 11, 10, 13, 5, 18, 6, 19, 10, 9, 6, 24, 6, 11, 11, 20, 9, 17, 6, 14, 10, 18, 4, 26, 7, 10, 11, 13, 9, 17, 4, 24, 17, 12, 9, 22
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OFFSET
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1,1
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LINKS
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FORMULA
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EXAMPLE
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7^8-1 = 5764800 = 2^6 * 3 * 5^2 * 1201 and a(8) = bigomega(5764800) = 6+1+2+1 = 10. - Bernard Schott, Feb 02 2020
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MATHEMATICA
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PrimeOmega[Table[7^n - 1, {n, 1, 30}]] (* Amiram Eldar, Feb 02 2020 *)
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PROG
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(Magma) f:=func<n|&+[p[2]: p in Factorization(n)]>; [f(7^n- 1):n in [1..85]]; // Marius A. Burtea, Feb 02 2020
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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