a(1) = least k such that 1/2+1/3+1/4+1/5 < H(k) - H(5); a(2) = least k such that H(a(1)) - H(5) < H(k) -H(a(1)), and for n > 2, a(n) = least k such that H(a(n-1)) - H(a(n-2)) > H(k) - H(a(n-1)), where H = harmonic number.
A228025
a(1) = least k such that 1/2+1/3+1/4+1/5 < H(k) - H(5); a(2) = least k such that H(a(1)) - H(5) < H(k) -H(a(1)), and for n > 2, a(n) = least k such that H(a(n-1)) - H(a(n-2)) > H(k) - H(a(n-1)), where H = harmonic number.
Terms
- a(0) =20a(1) =76a(2) =285a(3) =1065a(4) =3976a(5) =14840a(6) =55385a(7) =206701a(8) =771420a(9) =2878980a(10) =10744501a(11) =40099025a(12) =149651600a(13) =558507376a(14) =2084377905a(15) =7779004245a(16) =29031639076a(17) =108347552060a(18) =404358569165
External references
- oeis: A228025