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A046386
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Products of four distinct primes.
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13
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210, 330, 390, 462, 510, 546, 570, 690, 714, 770, 798, 858, 870, 910, 930, 966, 1110, 1122, 1155, 1190, 1218, 1230, 1254, 1290, 1302, 1326, 1330, 1365, 1410, 1430, 1482, 1518, 1554, 1590, 1610, 1722, 1770, 1785, 1794, 1806, 1830, 1870, 1914, 1938, 1974
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OFFSET
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1,1
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COMMENTS
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A squarefree subsequence of A033993. Numbers like 420=2^2*3*5*7 with at least one prime exponent >1 in the prime signature are excluded here. - R. J. Mathar, Apr 03 2011
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LINKS
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T. D. Noe, Table of n, a(n) for n=1..10000
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EXAMPLE
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210=2*3*5*7. 330=2*3*5*11. 390 =2*3*5*13. 462=2*3*7*11.
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MATHEMATICA
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fQ[n_] := Last /@ FactorInteger[n] == {1, 1, 1, 1}; Select[ Range[2000], fQ[ # ] &] (from Robert G. Wilson v, Aug 04 2005)
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CROSSREFS
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Cf. A046387, A067885 (product of 5 and 6 distinct primes, resp.)
Cf. A006881, A007304, A014613, A046402.
Sequence in context: A119427 A074159 A033993 * A046402 A147571 A121479
Adjacent sequences: A046383 A046384 A046385 * A046387 A046388 A046389
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KEYWORD
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nonn
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AUTHOR
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Patrick De Geest, Jun 15 1998.
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STATUS
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approved
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