|
| |
|
|
A001697
|
|
a(n+1)=a(n)(a(0)+ ... +a(n)).
(Formerly M1902 N0751)
|
|
3
| |
|
|
1, 1, 2, 8, 96, 10368, 108615168, 11798392572168192, 139202068568601556987554268864512, 19377215893777651167043206536157390321290709180447278572301746176
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 0,3
|
|
|
COMMENTS
| Number of binary trees of height n where for each node the left subtree is at least as high as the right subtree. - Franklin T. Adams-Watters, Feb 08 2007
|
|
|
REFERENCES
| N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
|
|
|
LINKS
| A. V. Aho and N. J. A. Sloane, Some doubly exponential sequences, Fib. Quart., 11 (1973), 429-437.
Index entries for sequences of form a(n+1)=a(n)^2 + ...
Index to divisibility sequences
|
|
|
PROG
| (PARI) a(n)=if(n<2, n >= 0, a(n-1)^2*(1+1/a(n-2)))
|
|
|
CROSSREFS
| a(n)=A039941(2*n+1); first difference sequence of A001696 is this sequence.
Cf. A002658, A001699.
Sequence in context: A137704 A001417 A156926 * A006069 A052457 A119654
Adjacent sequences: A001694 A001695 A001696 * A001698 A001699 A001700
|
|
|
KEYWORD
| nonn,easy,nice
|
|
|
AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
|
|
|
EXTENSIONS
| Additional comments from Michael Somos, May 19, 2000
|
| |
|
|
