login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A050605 Column/row 2 of A050602: a(n) = add3c(n,2). 5
0, 0, 1, 1, 0, 0, 2, 2, 0, 0, 1, 1, 0, 0, 3, 3, 0, 0, 1, 1, 0, 0, 2, 2, 0, 0, 1, 1, 0, 0, 4, 4, 0, 0, 1, 1, 0, 0, 2, 2, 0, 0, 1, 1, 0, 0, 3, 3, 0, 0, 1, 1, 0, 0, 2, 2, 0, 0, 1, 1, 0, 0, 5, 5, 0, 0, 1, 1, 0, 0, 2, 2, 0, 0, 1, 1, 0, 0, 3, 3, 0 (list; graph; refs; listen; history; internal format)
OFFSET

0,7

COMMENTS

It seems that (n-sum(k=1,n,a(k))/log(n) is bounded - Benoit Cloitre (benoit7848c(AT)orange.fr), Oct 03 2002

2^a(n) is the highest power of 2 dividing the n-th triangular number n*(n+1)/2 - Benoit Cloitre (benoit7848c(AT)orange.fr), Oct 03 2002

MAPLE

nmax:=80; with(Bits): add3c := proc(a, b) option remember; if(0 = And(a, b)) then RETURN(0); else RETURN(1+add3c(Xor(a, b), 2*And(a, b))); fi; end: for n from 0 to nmax do a(n):=add3c(n, 2) od: seq(a(n), n=0..nmax); [From Johannes W. Meijer (meijgia(AT)hotmail.com), Jun 18 2009]

PROG

(PARI) a(n)=valuation(n*(n+1)/2, 2)

CROSSREFS

Bisection gives column/row 1 of A050602: A007814.

Contribution from Johannes W. Meijer (meijgia(AT)hotmail.com), Jun 18 2009: (Start)

A050605(4*n+2) equals A001511(n).

Cf. A161737 and A069834.

(End)

Sequence in context: A055736 A006997 A141612 * A060571 A131555 A103822

Adjacent sequences:  A050602 A050603 A050604 * A050606 A050607 A050608

KEYWORD

nonn

AUTHOR

Antti Karttunen Jun 22 1999

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 13 22:36 EST 2012. Contains 205567 sequences.