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A375529
Lexicographically earliest sequence of positive integers a(1), a(2), a(3), ... such that for any n > 0, Sum_{k = 1..n} prime(k)/a(k) < 1.
4
3, 10, 151, 31711, 1580159131, 2950885219102973491, 11387023138265143513338462726052139311, 144918919004489964473283047921945994420315076260338720025368711042369934871
OFFSET
1,1
LINKS
N. J. A. Sloane, A Nasty Surprise in a Sequence and Other OEIS Stories, Experimental Mathematics Seminar, Rutgers University, Oct 10 2024, Youtube video; Slides [Mentions this sequence]
FORMULA
a(n) = prime(n)*A375530(n-1) + 1.
PROG
(PARI) B(u)={my(v=vector(#u)); my(r=1); for(i=1, #u, my(t=floor(u[i]/r)+1); v[i]=t; r-=u[i]/t); v}
a(n)={B(vector(n, k, prime(k)))[n]} \\ Andrew Howroyd, Sep 04 2024
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved