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A346136 a(n) is the number of iterations that n requires to reach 1 under the map n -> A346063(n). 0
2, 1, 2, 2, 3, 3, 1, 4, 1, 4, 3, 3, 4, 3, 2, 4, 4, 5, 2, 3, 9, 11, 8, 6, 10, 12, 6, 7, 2, 8, 4, 3, 6, 4, 10, 7, 2, 7, 4, 9, 4, 5, 4, 1, 8, 7, 6, 11, 2, 73, 5, 12, 5, 6, 1, 5, 2, 4, 34, 7, 5, 5, 2, 51, 7, 2, 5, 3, 5, 5, 3, 15, 6, 5, 2, 4, 10 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Conjecture: the sequence is infinite.

LINKS

Table of n, a(n) for n=1..77.

PROG

(Python)

from sympy import prime, isprime

for n in range(1, 78):

    m = prime(n); ct = 0

    while m:

        if isprime(m): m = m*m - 1; ct += 1

        else:

            m //= 2

            if m == 2: break

    print(ct)

CROSSREFS

Cf. A339991, A340008, A340418, A340419, A346063.

Sequence in context: A224493 A129193 A262446 * A205147 A319447 A224961

Adjacent sequences:  A346133 A346134 A346135 * A346137 A346138 A346139

KEYWORD

nonn,more

AUTHOR

Ya-Ping Lu, Jul 05 2021

STATUS

approved

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Last modified December 8 19:21 EST 2021. Contains 349596 sequences. (Running on oeis4.)