|
%I #16 Apr 23 2020 07:36:41
%S 836,7192,7912,9272,10792,17272,45356,73616,83312,91388,113072,222952,
%T 243892,254012,338572,343876,351956,388076,407132,410476,465652,
%U 470668,475684,477356,482372,490732,495748,500764,502436,507452,512468,515812
%N Weird numbers (A006037) not divisible by 5.
%C Up to 200000, there are only 11 weird numbers not divisible by 5.
%C 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 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 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 Amiram Eldar, <a href="/A138850/b138850.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..500 from M. F. Hasler)
%o (PARI) t=0; A138850=vector(50,i,until( (t+=2)%5 && is_A006037(t),);t) \\ [Updated by _M. F. Hasler_, Jan 07 2014]
%Y Cf. A006037, A100696.
%K nonn
%O 1,1
%A _M. F. Hasler_, Apr 02 2008
|
