A119350 First differences of A118374.

1, 1, 4, 1, 1, 1, 1, 6, 1, 1, 4, 1, 1, 1, 1, 1, 1, 1, 1, 10, 1, 1, 4, 1, 1, 1, 1, 6, 1, 1, 4, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 18, 1, 1, 4, 1, 1, 1, 1, 6, 1, 1, 4, 1, 1, 1, 1, 1, 1, 1, 1, 10, 1, 1, 4, 1, 1, 1, 1, 6, 1, 1, 4, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1

Offset

1,3

Links

Table of n, a(n) for n=1..104.

Formula

Conjecture. Define g(1)=1 and, for i>1, g(i)=2*g(i-1)+2^(i-2). Also define h(1)=1, h(2)=4 and, for i>2, h(i)=h(i-1)+2^(i-2). Then a(n)=h(i) if n=g(i), a(n)=1 if g(i)-2^(i-2)<=n<g(i) and a(n)=a(n-g(i-1)) if g(i-1)<n<g(i)-2^(i-2). (This has been verified for the first 1000 terms.)

Crossrefs

Cf. A118374, A114889, A114890.

Sequence in context: A046563 A046591 A361236 * A016528 A368884 A350388

Adjacent sequences: A119347 A119348 A119349 * A119351 A119352 A119353

Keyword

nonn

Author

John W. Layman, May 23 2006

Status

approved