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A354110
The 2-adic valuation of phi(A267099(n)), where A267099 is fully multiplicative involution swapping the positions of 4k+1 and 4k+3 primes, and phi is Euler totient function.
1
0, 0, 2, 1, 1, 2, 2, 2, 2, 1, 4, 3, 1, 2, 3, 3, 1, 2, 2, 2, 4, 4, 2, 4, 1, 1, 2, 3, 1, 3, 3, 4, 6, 1, 3, 3, 1, 2, 3, 3, 1, 4, 2, 5, 3, 2, 2, 5, 2, 1, 3, 2, 1, 2, 5, 4, 4, 1, 3, 4, 1, 3, 4, 5, 2, 6, 3, 2, 4, 3, 5, 4, 1, 1, 3, 3, 6, 3, 2, 4, 2, 1, 2, 5, 2, 2, 3, 6, 1, 3, 3, 3, 5, 2, 3, 6, 1, 2, 6, 2, 1, 3, 4, 3, 5
OFFSET
1,3
LINKS
FORMULA
a(n) = A007814(A354102(n)) = A053574(A267099(n)).
PROG
(PARI)
\\ Uses also the program from A267099:
A354102(n) = eulerphi(A267099(n));
A354110(n) = valuation(A354102(n), 2);
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 20 2022
STATUS
approved