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A318363
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Multiplicative with a(prime(i)^k) = prime(k)^2^(i-1).
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2
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1, 2, 4, 3, 16, 8, 256, 5, 9, 32, 65536, 12, 4294967296, 512, 64, 7, 18446744073709551616, 18, 340282366920938463463374607431768211456, 48, 1024, 131072, 115792089237316195423570985008687907853269984665640564039457584007913129639936, 20, 81, 8589934592, 25
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OFFSET
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1,2
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COMMENTS
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This sequence has similarities with A048767.
This sequence is injective (all terms are distinct).
This sequence is a permutation of A268375.
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LINKS
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FORMULA
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MATHEMATICA
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Array[Apply[Times, FactorInteger[#] /. {p_, k_} /; p > 1 :> Prime[k]^2^(PrimePi[p] - 1)] &, 27] /. {1, 1} -> 1 (* Michael De Vlieger, Aug 25 2018 *)
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PROG
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(PARI) a(n) = my (f=factor(n)); prod(i=1, #f~, prime(f[i, 2])^2^(primepi(f[i, 1])-1))
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CROSSREFS
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KEYWORD
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nonn,mult
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AUTHOR
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STATUS
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approved
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