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A061509
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Write n in decimal, omit 0's, replace the k-th digit d[k] with the k-th prime, raised to d[k]-th power and multiply.
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6
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1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 2, 6, 18, 54, 162, 486, 1458, 4374, 13122, 39366, 4, 12, 36, 108, 324, 972, 2916, 8748, 26244, 78732, 8, 24, 72, 216, 648, 1944, 5832, 17496, 52488, 157464, 16, 48, 144, 432, 1296, 3888, 11664, 34992, 104976, 314928
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OFFSET
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0,2
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COMMENTS
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Not the same as A189398: see formula.
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LINKS
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FORMULA
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a(n) = a(n*10^k). a((10^k-1)/9) = primorial(k) = A002110(k).
If n=d[1]d[2]...d[m] in decimal (0<d[k]<10: m nonzero digits), then a(n)=p[1]^d[1]*...*p[m]^d[m], where p[k] is the k-th prime. - M. F. Hasler, Aug 16 2014
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EXAMPLE
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a(4) = 2^4 = 16, a(123) = (2^1)*(3^2)*(5^3) = 2250.
For n = 0, the list of nonzero digits is empty, and the empty product equals 1.
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PROG
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(Haskell)
a061509 n = product $ zipWith (^)
a000040_list (map digitToInt $ filter (/= '0') $ show n)
(PARI) A061509(n)=prod(k=1, #n=select(t->t, digits(n)), prime(k)^n[k]) \\ M. F. Hasler, Aug 16 2014
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CROSSREFS
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KEYWORD
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base,less,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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