id:A071523 - OEIS Search Results

Search: id:A071523

Displaying 1-1 of 1 results found.

page 1

Number of 11-smooth numbers <= n.

+0
1

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 12, 13, 14, 15, 15, 16, 16, 17, 18, 19, 19, 20, 21, 21, 22, 23, 23, 24, 24, 25, 26, 26, 27, 28, 28, 28, 28, 29, 29, 30, 30, 31, 32, 32, 32, 33, 34, 35, 35, 35, 35, 36, 37, 38, 38, 38, 38, 39, 39, 39, 40, 41, 41, 42, 42, 42, 42, 43, 43, 44 (list; graph; listen)

	OFFSET	`1,2`
	COMMENT	`An 11-smooth number is a number of the form 2^x3^y5^z7^u11^v (x,y,z,u,v) >= 0.`
	FORMULA	`a(n) = Card{ k \| A051038(k) <= n }`
	PROGRAM	`(PARI) a(n)=sum(k=1, n, (k<4)\|13>vecmax(factor(k)~[1, ]))`
	CROSSREFS	`Sequence in context: A087999 A106614 A043272 this_sequence A070696 A053834 A043273` `Adjacent sequences: A071520 A071521 A071522 this_sequence A071524 A071525 A071526`
	KEYWORD	`easy,nonn`
	AUTHOR	`Benoit Cloitre (benoit7848c(AT)orange.fr), Jun 02 2002`

page 1

Search completed in 0.002 seconds

Last modified November 25 08:46 EST 2009. Contains 167481 sequences.

AT&T Labs Research