A139386 First gap of length at least n in A007950, lower end.

1, 5, 5, 37, 37, 187, 187, 821, 821, 821, 821, 13301, 13301, 109941, 109941, 522717, 522717, 522717, 522717, 1247282901, 1247282901

Offset

1,2

Comments

All terms of A007950 are odd, therefore all gaps in A007950 have odd length and a(2*k) = a(2*k+1) for k >= 1.

a(22) > 10^11. - Donovan Johnson

Links

Table of n, a(n) for n=1..21.

Example

First few terms of A007950 are 1,3,5,9,11, ... . The first gap of length 1 is between 1 and 3, so a(1) = 1; the first gap of length 2 is between 5 and 9; it has length 3, so a(2) = a(3) = 5.

Crossrefs

Cf. A007950, A138845, A138900, A139387.

Sequence in context: A269814 A270018 A269876 * A074947 A099757 A271091

Adjacent sequences: A139383 A139384 A139385 * A139387 A139388 A139389

Keyword

nonn,more

Author

Klaus Brockhaus, Apr 17 2008

Extensions

a(20)-a(21) from Donovan Johnson, Dec 27 2010

Status

approved