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A139386
First gap of length at least n in A007950, lower end.
1
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
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
KEYWORD
nonn,more
AUTHOR
Klaus Brockhaus, Apr 17 2008
EXTENSIONS
a(20)-a(21) from Donovan Johnson, Dec 27 2010
STATUS
approved