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A165425
a(1) = 1, a(2) = 7, a(n) = product of the previous terms for n >= 3.
6
1, 7, 7, 49, 2401, 5764801, 33232930569601, 1104427674243920646305299201, 1219760487635835700138573862562971820755615294131238401
OFFSET
1,2
LINKS
FORMULA
a(1) = 1, a(2) = 7, a(n) = Product_{i=1..n-1} a(i), n >= 3.
a(1) = 1, a(2) = 7, a(n) = A000420(2^(n-3)) = 7^(2^(n-3)), n >= 3.
a(1) = 1, a(2) = 7, a(3) = 7, a(n) = (a(n-1))^2, n >= 4.
MATHEMATICA
a[1]:= 1; a[2]:= 7; 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, 7, prod(j=1, n-1, a(j))))};
for(n=1, 10, print1(a(n), ", ")) \\ G. C. Greubel, Oct 19 2018
CROSSREFS
Sequence in context: A222462 A214887 A203066 * A220079 A153272 A117860
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Sep 17 2009
EXTENSIONS
More terms from Vincenzo Librandi, Apr 21 2010
STATUS
approved