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A364824
Index of prime(n) in A067836, or -1 if prime(n) does not occur in it.
1
1, 2, 3, 4, 6, 5, 7, 8, 9, 12, 13, 10, 19, 14, 20, 16, 26, 42, 18, 25, 11, 15, 17, 43, 118, 33, 24, 31, 29, 212, 40, 68, 30, 98, 22, 45, 34, 109, 28, 39, 21, 23, 46, 143, 27, 35, 37, 55, 47, 123, 58, 90, 132, 32, 139, 91, 41, 44, 38, 52, 36, 77, 54, 48, 53, 83, 51
OFFSET
1,2
COMMENTS
All terms in A067836 are distinct, making this sequence defined.
If the conjecture holds that A067836 contains only primes, then a(A062894(n)) = n.
If all primes eventually occur in A067836, then all terms in this sequence are positive and A062894(a(n)) = n.
PROG
(Python)
from itertools import count
from sympy import prime, nextprime
def A364824(n):
a, f, p = 2, 1, prime(n)
for i in count(1):
if a == p:
return i
a=nextprime((f:=f*a)+1)-f # Chai Wah Wu, Sep 09 2023
CROSSREFS
Sequence in context: A121730 A275659 A244321 * A062894 A339723 A129606
KEYWORD
nonn
AUTHOR
Bert Dobbelaere, Aug 09 2023
STATUS
approved