OFFSET
1,1
REFERENCES
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
Delbert L. Johnson, Table of n, a(n) for n = 1..11
D. S. Kluk and N. J. A. Sloane, Correspondence, 1979.
FORMULA
a(n) = A001045(2^n+1) = (3*a(n-1)^2 + 1)/2 - a(n-1). - Michael Somos, Mar 30 2020
a(n) = A070969(n)/3. - Alois P. Heinz, Mar 28 2023
MATHEMATICA
lst={}; Do[AppendTo[lst, (2^(2^n+1)+1)/3], {n, 9}]; lst (* Vladimir Joseph Stephan Orlovsky, Sep 19 2008 *)
Table[(1+2^(2^n+1))/3, {n, 10}] (* Harvey P. Dale, Apr 03 2023 *)
PROG
(PARI) {a(n) = if(n > 0, (2^(2^n + 1) + 1)/3, 0)}; /* Michael Somos, Mar 30 2020 */
CROSSREFS
KEYWORD
nonn
AUTHOR
Dennis S. Kluk (mathemagician(AT)ameritech.net)
STATUS
approved