A393778 - OEIS

%I #10 Mar 10 2026 16:24:31

%S 4,3,0,2,9,3,2,6,8,2,2,7,7,5,7,2,8,0,4,1,9,7,7,1,2,2,2,2,2,4,7,3,9,7,

%T 1,5,3,3,0,5,7,5,1,0,9,9,4,5,3,4,9,3,8,7,9,2,8,0,4,7,6,2,8,9,6,7,5,4,

%U 9,8,8,1,0,6,7,1,3,6,3,2,9,4,7,1,7,8,7,5,6,2,1,1,6,7,1,2,0,9,7,8,2,9,7,5,0,1

%N Decimal expansion 1/zeta(2)^2 + Sum_{k>=2} (1/zeta(k) - 1/zeta(k+1))^2.

%C The asymptotic probability that two positive integers selected independently at random have equal maximum exponents in their prime factorizations (A051903).

%e 0.430293268227757280419771222224739715330575109945349...

%o (PARI) 1/zeta(2)^2 + sumpos(k = 2, (1/zeta(k) - 1/zeta(k+1))^2)

%Y Cf. A033150, A051903, A227929, A357310.

%K nonn,cons

%O 0,1

%A _Amiram Eldar_, Feb 27 2026