A340819 Denominators of a sequence of fractions converging to A340820, the asymptotic density of numbers whose excess of prime divisors (A046660) is even (A162644).

6, 9, 54, 4, 264, 308, 7854, 374, 1564, 11339, 362848, 127541072, 1307295988, 2614591976, 42742894912, 1132686715168, 4608863185856, 71437379380768, 162734350229389504, 46216555465146619136, 427503138052606227008, 270181983249247135469056, 64347502466822129824768

Offset

1,1

Comments

See A340818 for details.

Links

Amiram Eldar, Table of n, a(n) for n = 1..462

Mathematica

d[p_] := 1/(p*(p + 1)); delta[n_] := delta[n] = d[Prime[n]]; f[0] = 1; f[n_] := f[n] = f[n - 1] * (1 - delta[n]) + (1 - f[n - 1]) * delta[n]; Denominator @ Array[f, 30]

Crossrefs

Cf. A046660, A162644, A340818 (numerators), A340820.

Sequence in context: A177181 A126110 A372499 * A254207 A098662 A056425

Adjacent sequences: A340816 A340817 A340818 * A340820 A340821 A340822

Keyword

nonn,frac

Author

Amiram Eldar, Jan 22 2021

Status

approved