A080023 log_phi(n) is closer to an integer than is log_phi(m) for any m with 2<=m<n, where phi=(1+sqrt(5))/2 is the golden ratio.

2, 3, 4, 7, 11, 18, 29, 47, 76, 123, 199, 322, 521, 843, 1364, 2207, 3571, 5778, 9349, 15127, 24476, 39603, 64079, 103682, 167761, 271443, 439204, 710647, 1149851, 1860498, 3010349, 4870847, 7881196, 12752043, 20633239, 33385282, 54018521

Offset

1,1

Comments

This is the sequence of Lucas numbers (A000032) without the term 1.

References

Suggested by Neil Fernandez, Jan 19 2003

Links

Table of n, a(n) for n=1..37.

Example

log_phi(2) = 1+0.440..., log_phi(3) = 2+0.283..., log_phi(4) = 3-0.119..., log_phi(7) = 4+0.0437...

Prog

(PARI) lista(nn) = {flmin = 1; phi = (1 + sqrt(5))/2; for (i = 2, nn, li = log(i)/log(phi); fli = abs(round(li) - li); if (fli < flmin, print1(i, ", "); flmin = fli; ); ); } \\ Michel Marcus, Aug 29 2013

Crossrefs

Cf. A000032, A080021, A080022.

Sequence in context: A222331 A222332 A222333 * A169985 A254729 A293544

Adjacent sequences: A080020 A080021 A080022 * A080024 A080025 A080026

Keyword

nonn,easy

Author

Dean Hickerson, Jan 20 2003

Status

approved