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%I #12 Dec 23 2021 21:49:23
%S 735,819,1035,1196,1274,1275,1449,1665,1924,1925,1952,1988,2324,2331,
%T 2540,2655,3068,3195,3267,3324,3339,3549,3555,3626,3717,4164,4220,
%U 4235,4556,4563,4598,4635,4675,4796,5024,5084,5324,5525,5588,5634,5660,6003
%N Numbers k such that d(k) = d(k+1) = 12.
%H Zak Seidov, <a href="/A174456/b174456.txt">Table of n, a(n) for n = 1..71998</a>
%e a(1) = 735 = A030630(67) = A030630(68) - 1 = A005237(88);
%e a(2) = 819 = A030630(76) = A030630(77) - 1 = A005237(99);
%e a(3) = 1035 = A030630(100) = A030630(101) - 1 = A005237(124).
%t Select[Range[10^7],DivisorSigma[0,{#,#+1}]=={12,12}&]
%t Transpose[SequencePosition[DivisorSigma[0,Range[6500]],{12,12}]][[1]] (* The program uses the SequencePosition function from Mathematica version 10 *) (* _Harvey P. Dale_, Jul 16 2016 *)
%o (PARI) is(n)=numdiv(n)==12 && numdiv(n+1)==12 \\ _Charles R Greathouse IV_, Jun 19 2016
%Y Intersection of A005237 and A030630.
%K nonn
%O 1,1
%A _Zak Seidov_, May 25 2010
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