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A350778
Numerators of fractions n/prime(n) sorted in decreasing order.
2
2, 3, 4, 1, 6, 5, 8, 7, 9, 11, 10, 14, 12, 15, 13, 16, 18, 17, 21, 19, 20, 22, 23, 24, 29, 30, 27, 28, 25, 26, 34, 32, 31, 33, 36, 37, 35, 39, 38, 42, 40, 46, 41, 45, 44, 43, 47, 53, 51, 50, 52, 49, 61, 48, 54, 58, 55, 60, 59, 56, 57, 62, 66, 65, 64, 63, 67, 68, 71, 70
OFFSET
1,1
COMMENTS
A permutation of the positive integers. Computation of the first n terms of the sequence requires the generation and sorting of more than n fractions; exactly how many more is an open question.
MATHEMATICA
Take[Numerator[ReverseSort[Table[n/Prime[n], {n, 1, 100+10}]]], 100]
PROG
(Python)
from fractions import Fraction
from sympy import prime, primerange
def aupton(N, m=3): # m is safety factor
f = (Fraction(i, p) for i, p in enumerate(primerange(2, prime(m*N)), 1))
return [fn.numerator for fn in sorted(f, reverse=True)][:N]
print(aupton(100)) # Michael S. Branicky, Jan 15 2022
(PARI) lista(nn) = Vec(apply(numerator, vecsort(vector(3*nn, n, n/prime(n)), , 4)), nn); \\ Michel Marcus, Jan 17 2022
CROSSREFS
Sequence in context: A065338 A316272 A294649 * A001438 A342410 A345937
KEYWORD
nonn,easy,frac
AUTHOR
Petr Platais, Jan 15 2022
STATUS
approved