A068221 An auxiliary bit-mask sequence for computing A066425. (The "clean", symmetric one).

1, 3, 27, 6939, 1819024155, 4000076419257644882715, 77372730618755190082837640023742562619343248155, 237146729315719909074685533605289611245100501015339264129426202250460094330698830235303562543675218715

Offset

1,2

Links

Table of n, a(n) for n=1..8.

A. Karttunen, Scheme functions for computing A066425 and related sequences.

Formula

a(1)=1, a(n) = ((2^(A068739(n-1)+A068059(n-1)-1))+1)*a(n-1)

Crossrefs

The corresponding "dirty" bit-mask sequence is A068222. This sequence in binary: A068223. The width of these bit-masks is given by A068739.

Sequence in context: A122215 A122217 A316368 * A068222 A308384 A055777

Adjacent sequences: A068218 A068219 A068220 * A068222 A068223 A068224

Keyword

nonn

Author

Antti Karttunen, Feb 26 2002

Status

approved