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A306951 Number of weird numbers (A006037) below 10^n. 0
0, 1, 2, 7, 204, 1765, 15554, 173709, 1756426, 17270452 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

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...?

LINKS

Table of n, a(n) for n=1..10.

S. J. Benkoski and P. Erdős, On weird and pseudoperfect numbers, Math. Comp., 28 (1974), pp. 617-623. Alternate link; 1975 corrigendum

EXAMPLE

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

CROSSREFS

Cf. A006037, A275487, A275491, A302992.

Sequence in context: A307582 A125610 A247028 * A181864 A096463 A048560

Adjacent sequences:  A306948 A306949 A306950 * A306952 A306953 A306954

KEYWORD

nonn,more

AUTHOR

Amiram Eldar, Mar 17 2019

STATUS

approved

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Last modified November 15 18:29 EST 2019. Contains 329149 sequences. (Running on oeis4.)