%I A138850
%S A138850 836,7192,7912,9272,10792,17272,45356,73616,83312,91388,113072,222952,
%T A138850 243892,254012,338572,343876,351956,388076,407132,410476,465652,470668,
%U A138850 475684,477356,482372,490732,495748,500764,502436,507452,512468,515812
%N A138850 Weird numbers (A006037) not divisible by 5.
%C A138850 Up to 200000, there are only 11 weird numbers not divisible by 5.
%C A138850 Since no A006037(k) < 10^17 is odd, at least up to there, "divisible
by 5" is equivalent to "ending in 0" (in base 10).
%C A138850 It appears that 4*11*19*p is an element of this sequence for p=1 and
all primes p>547. Moreover, these seem to comprise most of the terms
of this sequence.
%C A138850 Up to n=500, the only indices for which a(n) is not of this form are
n=2,...,16, 18, 34, 38, 43, 64, 83, 148, 158, 236, 266, 296, 310.
%H A138850 M. F. Hasler, <a href="b138850.txt">Table of n, a(n) for n=1,...,500</
a>.
%o A138850 (PARI) t=0; A138850=vector(50,i,until( (t+=2)%5 & isA006037(t),);t)
%Y A138850 Cf. A006037 (weird numbers), A100696 (a puzzle).
%Y A138850 Sequence in context: A095257 A113856 A162945 this_sequence A016113 A167603
A118380
%Y A138850 Adjacent sequences: A138847 A138848 A138849 this_sequence A138851 A138852
A138853
%K A138850 nonn
%O A138850 1,1
%A A138850 M. F. Hasler (www.univ-ag.fr/~mhasler), Apr 02 2008
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