A038755 Earliest sequence where a(a(n))=2^n.

3, 8, 2, 256, 6, 32, 9, 4, 128, 11, 1024, 13, 4096, 15, 16384

Offset

1,1

Links

Table of n, a(n) for n=1..15.

Index entries for sequences of the a(a(n)) = 2n family

Example

a(9)=a(a(7))=2^7=128, a(16)=a(2^4)=a(a(a(4)))=a(a(256))=2^256>10^77

Crossrefs

Cf. A038756, A038757.

Sequence in context: A138714 A336054 A341814 * A245171 A011230 A245168

Adjacent sequences: A038752 A038753 A038754 * A038756 A038757 A038758

Keyword

nonn

Author

Henry Bottomley, May 03 2000

Status

approved