login
A165423
a(1) = 1, a(2) = 5, a(n) = product of the previous terms for n >= 3.
4
1, 5, 5, 25, 625, 390625, 152587890625, 23283064365386962890625, 542101086242752217003726400434970855712890625
OFFSET
1,2
LINKS
FORMULA
a(1) = 1, a(2) = 5, a(n) = Product_{i=1..n-1} a(i), n >= 3.
a(1) = 1, a(2) = 5, a(n) = A000351(2^(n-3)) = 5^(2^(n-3)), n >= 3.
a(1) = 1, a(2) = 5, a(3) = 5, a(n) = (a(n-1))^2, n >= 4.
MATHEMATICA
a[1]:= 1; a[2]:= 5; a[n_]:= Product[a[j], {j, 1, n-1}]; Table[a[n], {n, 1, 12}] (* G. C. Greubel, Oct 19 2018 *)
PROG
(PARI) {a(n) = if(n==1, 1, if(n==2, 5, prod(j=1, n-1, a(j))))};
for(n=1, 10, print1(a(n), ", ")) \\ G. C. Greubel, Oct 19 2018
CROSSREFS
Sequence in context: A222281 A214706 A203191 * A220078 A302000 A219351
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Sep 17 2009
STATUS
approved