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A306951 Number of weird numbers (A006037) below 10^n. 0

%I #11 May 26 2023 05:46:28

%S 0,1,2,7,204,1765,15554,173709,1756426,17270452,172559761

%N Number of weird numbers (A006037) below 10^n.

%C Benkoski and Erdős proved that the asymptotic density of weird numbers is positive, thus lim_{n->oo} a(n)/10^n = c > 0. Is c = 0.0017...?

%H S. J. Benkoski and P. Erdős, <a href="https://doi.org/10.1090/S0025-5718-1974-0347726-9">On weird and pseudoperfect numbers</a>, Math. Comp., 28 (1974), pp. 617-623. <a href="http://www.renyi.hu/~p_erdos/1974-24.pdf">Alternate link</a>; <a href="https://doi.org/10.1090/S0025-5718-1975-0360452-6">1975 corrigendum</a>.

%e The only weird number below 100 is 70 which is larger than 10, thus a(1) = 0 and a(2) = 1.

%Y Cf. A006037, A275487, A275491, A302992.

%K nonn,more

%O 1,3

%A _Amiram Eldar_, Mar 17 2019

%E a(11) from _Amiram Eldar_, May 26 2023

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Last modified April 19 07:11 EDT 2024. Contains 371782 sequences. (Running on oeis4.)