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A277195
Permutation of nonnegative integers: a(n) = A022290(A277010(n)).
4
0, 1, 2, 3, 4, 5, 6, 8, 13, 9, 7, 21, 34, 10, 14, 55, 22, 89, 12, 144, 15, 35, 11, 233, 56, 23, 377, 17, 610, 90, 987, 36, 1597, 16, 57, 145, 2584, 4181, 234, 24, 25, 6765, 91, 19, 10946, 17711, 378, 18, 38, 28657, 611, 46368, 37, 988, 146, 75025, 26, 235, 1598, 58, 121393, 196418, 59, 317811, 20, 2585, 514229, 832040, 27, 379, 1346269, 93, 92
OFFSET
1,3
COMMENTS
Note the indexing: domain starts from 1, but the range includes also 0.
FORMULA
PROG
(Scheme) (define (A277195 n) (A022290 (A277010 n)))
(Python)
from math import isqrt
from sympy import fibonacci, mobius, primepi, factorint
def A277195(n):
def f(x): return n+x-sum(mobius(k)*(x//k**2) for k in range(1, isqrt(x)+1))
def bisection(f, kmin=0, kmax=1):
while f(kmax) > kmax: kmax <<= 1
while kmax-kmin > 1:
kmid = kmax+kmin>>1
if f(kmid) <= kmid:
kmax = kmid
else:
kmin = kmid
return kmax
return sum(fibonacci(primepi(p)+i) for i, p in enumerate(factorint(bisection(f), multiple=True), 1)) # Chai Wah Wu, Aug 31 2024
CROSSREFS
Inverse: A277196.
Sequence in context: A337448 A019532 A008537 * A358208 A133430 A033071
KEYWORD
nonn
AUTHOR
Antti Karttunen, Oct 07 2016
STATUS
approved