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%I #8 Feb 11 2019 01:19:23
%S 19,51,243,244,424,476,604,638,723,846,926,1683,1774,2008,2524,2526,
%T 2528,3124,3176,3178,4204,4476,4526,4924,5824,6726,6812,6963,7300,
%U 7443,7676,8426,8958,8974,9458,9926,10052,10083,10468,11674,11710,12428,12483,12592
%N Numbers n such that d(n-1) = d(n+1) = 6, where d(k) is the number of divisors of k (A000005).
%H Nathaniel Johnston, <a href="/A190267/b190267.txt">Table of n, a(n) for n = 1..2500</a>
%p with(numtheory): A190267 := proc(n) option remember: local k: if(n=1)then return 19:else k:=procname(n-1)+1: do if(tau(k-1)=6 and tau(k+1)=6)then return k: fi: k:=k+1: od: fi: end: seq(A190267(n), n=1..44); # _Nathaniel Johnston_, May 06 2011
%Y Cf. A030515, A189974.
%K nonn
%O 1,1
%A _Juri-Stepan Gerasimov_, May 06 2011
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