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A344946 x -> prime(x) iterated prime(n) times, evaluated at n. 1
3, 11, 709, 167449, 88362852307, 156740126985437, 1172447586903041169661 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
FORMULA
a(n) = prime^{prime(n)}(n), with prime^{0}(n) = n and prime^{k}(n) = prime(prime^{k-1}(n)) for 1 <= k <= prime(n).
a(n) = prime(prime(...(n))) {prime(n) times}.
EXAMPLE
a(1) = prime(prime(1)) = 3.
a(2) = prime(prime(prime(2))) = 11.
a(3) = prime(prime(prime(prime(prime(3))))) = 709.
MATHEMATICA
nterms=6; Table[Nest[Prime[#]&, n, Prime[n]], {n, nterms}]
PROG
(Python)
from sympy import prime
def a(n):
iter = pn = prime(n)
for i in range(1, pn): iter = prime(iter)
return iter
print([a(n) for n in range(1, 6)]) # Michael S. Branicky, Jun 03 2021
(PARI) a(n) = my(p = n); for (k=1, prime(n), p=prime(p)); p; \\ Michel Marcus, Jun 03 2021
CROSSREFS
Sequence in context: A264725 A374558 A088579 * A368618 A374718 A006938
KEYWORD
nonn,more,hard
AUTHOR
Paolo Xausa, Jun 03 2021
EXTENSIONS
a(7) from Jinyuan Wang, Jul 12 2021
STATUS
approved

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Last modified August 20 17:50 EDT 2024. Contains 375337 sequences. (Running on oeis4.)