522717domain: NAppears in sequencesFirst gap of length at least n in A007950, lower end.at n=15A139386First gap of length at least n in A007950, lower end.at n=16A139386First gap of length at least n in A007950, lower end.at n=17A139386First gap of length at least n in A007950, lower end.at n=18A139386