A139386 - OEIS

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

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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 A374652

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