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A114993
(n-th 4-almost prime)^(n-th 4-almost prime).
0
18446744073709551616, 1333735776850284124449081472843776, 106387358923716524807713475752456393740167855629859291136, 12089258196146291747061760000000000000000000000000000000000000000
OFFSET
1,1
COMMENTS
4-almost prime analog of A051674. A114850 is semiprime analog of A051674. a(5) = 56^56 has 94 digits.
FORMULA
a(n) = A014613(n)^A014613(n).
EXAMPLE
a(1) = A014613(1)^A014613(1) = 16^16 = 18446744073709551616 = 2^64.
a(2) = A014613(2)^A014613(2) = 24^24 = 1333735776850284124449081472843776 = 2^72 * 3^24.
a(3) = A014613(3)^A014613(3) = 36^36 = 2^72 * 3^72.
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Jonathan Vos Post, Feb 22 2006
STATUS
approved