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A225295
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Pandigital numbers with exactly 4 prime factors (with multiplicity).
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1
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1023456987, 1023458679, 1023458967, 1023465798, 1023465897, 1023465978, 1023465987, 1023467589, 1023467859, 1023468579, 1023468597, 1023468795, 1023469758, 1023478569, 1023479586, 1023479865, 1023485967, 1023486579, 1023486957, 1023487659, 1023487965, 1023489657, 1023495678
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OFFSET
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1,1
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LINKS
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Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
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FORMULA
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A014613 INTERSECTION A171102.
a(n) ~ 6n log n / (log log n)^3. - Charles R Greathouse IV, May 04 2013
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EXAMPLE
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a(1) = 1023456987 = 3^2 * 7 * 16245349.
a(2) = 1023458679 = 3^3 * 37905877.
a(3) = 1023458967 = 3^2 * 113 * 1006351.
a(4) = 1023465897 = 3^2 * 6379 * 17827.
a(5) = 1023465987 = 3^2 * 53 * 2145631.
a(511032) = 10123456987 = 7^2 * 9833 * 21011.
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PROG
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(PARI) is(n)=#vecsort(digits(n), , 8)>9 && bigomega(n)==4 \\ Charles R Greathouse IV, May 04 2013
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CROSSREFS
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Cf. A001358, A014613, A221646.
Cf. A050288 (pandigital primes), A175845 (pandigital numbers).
Cf. A171102 (3-almost primes).
Sequence in context: A204047 A051264 A175845 * A036745 A225218 A268312
Adjacent sequences: A225292 A225293 A225294 * A225296 A225297 A225298
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KEYWORD
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nonn,base,easy
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AUTHOR
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Jonathan Vos Post, May 04 2013
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EXTENSIONS
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a(6)-a(23) from Charles R Greathouse IV, May 04 2013
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STATUS
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approved
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