A171481 a(n) = a(a(n-1)) + a(n - a(n-1) - 2) with a(0) = 0, a(1) = a(2) = 1.

0, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 4, 5, 5, 5, 5, 5, 5, 6, 6, 7, 7, 7, 7, 7, 7, 7, 8, 9, 9, 9, 10, 10, 10, 10, 10, 10, 10, 10, 11, 11, 12, 12, 12, 12, 13, 14, 15, 15, 15, 15, 15, 15, 15, 15, 15, 16, 16, 16, 17, 17, 17, 17, 17, 18, 18, 19, 19, 20, 21, 21, 21, 21, 21, 21, 21, 21, 21

Offset

0,5

Comments

Conjecture 1: a(n) - a(n-1) = 0 or 1.

Conjecture 2: lim_{n->infinity} a(n)/n = e/10.

Links

Paolo P. Lava, Table of n, a(n) for n = 0..10000

Maple

A171481 := proc(n) option remember; if n = 0 then 0; elif n <=2 then 1; else procname(procname(n-1)) +procname(n-procname(n-1)-2) ; end if; end proc: seq(A171481(n), n=0..100) ; # R. J. Mathar, Mar 16 2010

Crossrefs

Hofstadter-Conway-like sequence (see A004001).

Sequence in context: A367194 A135297 A176146 * A230775 A108037 A237354

Adjacent sequences: A171478 A171479 A171480 * A171482 A171483 A171484

Keyword

nonn

Author

Jaroslav Krizek, Dec 09 2009

Extensions

More terms from R. J. Mathar, Mar 16 2010

Status

approved