id:A107680 - OEIS Search Results

Search: id:A107680

Displaying 1-1 of 1 results found.

page 1

Repeating k-th ternary repunit 2^k times for k>0.

+0
4

1, 1, 4, 4, 4, 4, 13, 13, 13, 13, 13, 13, 13, 13, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121 (list; graph; listen)

	OFFSET	`1,3`
	COMMENT	`A032924(n) = a(n) + A107681(n);` `a(n) = greatest ternary repunit that is not greater than the n-th number with no 2 in ternary representation;` `A081604(A107681(n)) <= A081604(a(n)) = A081604(A032924(n)) = A000523(n+1).`
	FORMULA	`a(n) = A003462(A000523(n+1)).`
	EXAMPLE	`k=1: A003462(1) = (3^1-1)/2 = 1, therefore a(1) = a(2^1) = 1;` `k=2: A003462(2) = (3^2-1)/2 = 4, therefore a(2+1) = a(2+2) =` `a(2+3) = a(2+2^2) = 4.`
	CROSSREFS	`Cf. A007089.` `Sequence in context: A013189 A035621 A046109 this_sequence A134660 A132383 A115639` `Adjacent sequences: A107677 A107678 A107679 this_sequence A107681 A107682 A107683`
	KEYWORD	`nonn`
	AUTHOR	`Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), May 20 2005`
	EXTENSIONS	`Corrected by T. D. Noe (noe(AT)sspectra.com), Oct 25 2006`

page 1

Search completed in 0.004 seconds

Last modified December 19 12:50 EST 2009. Contains 171053 sequences.

AT&T Labs Research