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A377205
Lexicographically earliest sequence of positive integers a(1), a(2), ... such that for any n >= 0, s(n) = Sum_{k=1..n} 1/(k^2*a(k)) < 1.
3
2, 1, 1, 1, 1, 1, 3, 9, 171, 122014, 17661589931, 412924014578486602517, 1248808068140660770289141544749321839183623, 4529027355107615424925871833487047912228337079416162414871862143803627237910792872226
OFFSET
1,1
LINKS
EXAMPLE
s(0), s(1), ... = 0, 1/2, 3/4, 31/36, 133/144, 3469/3600, 3569/3600, ... .
MAPLE
s:= proc(n) option remember; `if`(n=0, 0, s(n-1)+1/(n^2*a(n))) end:
a:= proc(n) option remember; 1+floor(1/((1-s(n-1))*n^2)) end:
seq(a(n), n=1..14);
CROSSREFS
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Oct 19 2024
STATUS
approved