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A133808 Numbers that are primally tight, have 2 as first prime and weakly ascending powers. 7
1, 2, 4, 6, 8, 16, 18, 30, 32, 36, 54, 64, 108, 128, 150, 162, 210, 216, 256, 324, 450, 486, 512, 648, 750, 900, 972, 1024, 1296, 1458, 1470, 1944, 2048, 2250, 2310, 2916, 3750, 3888, 4096, 4374, 4500, 5832, 6750, 7350, 7776, 8192, 8748, 10290, 11250 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

All numbers of the form 2^k1*p_2^k2*...*p_n^k_n, where k1 <= k2 <= ... <= k_n and the p_i are the n first primes.

Subset of A073491,A133810.

CROSSREFS

Cf. A025487, A087980, A073491, A133809-A133813.

Sequence in context: A073935 A073696 A058602 * A160560 A093109 A070034

Adjacent sequences:  A133805 A133806 A133807 * A133809 A133810 A133811

KEYWORD

nonn

AUTHOR

Olivier Gerard (olivier.gerard(AT)gmail.com), Sep 23, 2007

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Last modified February 14 02:39 EST 2012. Contains 205567 sequences.