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%I #28 Apr 29 2018 02:19:56
%S 62,74,134,146,164,188,194,206,254,274,278,284,314,356,362,386,398,
%T 404,422,428,454,458,482,494,524,538,554,566,584,614,626,662,674,692,
%U 734,746,758,764,794,818,824,854,866,890,914,926,934,944,956,974,998,1004,1028
%N Even n where d(n) < d(n+1), where d(n) = number of positive divisors of n.
%C Terms calculated by _M. F. Hasler_.
%C First term == 0 (mod 6) is a(133) = 2274. - _Jianing Song_, Apr 03 2018
%H Jianing Song and Muniru A Asiru, <a href="/A138172/b138172.txt">Table of n, a(n) for n = 1..10000</a>(Terms 1 through 1019 from Jianing Song)
%p with(numtheory): A138172:=n->`if`(n mod 2 = 0 and tau(n) < tau(n+1), n, NULL): seq(A138172(n), n=1..1000); # _Wesley Ivan Hurt_, Apr 10 2015
%t 2 Position[Partition[Array[DivisorSigma[0, #] &, 10^3, 2], 2, 2], _?(#1 < #2 & @@ # &)][[All, 1]] (* _Michael De Vlieger_, Apr 07 2018 *)
%o (PARI) lista(nn) = {forstep(n=2, nn, 2, if (numdiv(n) < numdiv(n+1), print1(n, ", ")););} \\ _Michel Marcus_, Apr 10 2015
%o (GAP) Filtered([2,4..1300],n->Tau(n)<Tau(n+1)); # _Muniru A Asiru_, Apr 05 2018
%Y Cf. A000005, A138046, A138171.
%K nonn
%O 1,1
%A _Leroy Quet_, Mar 03 2008
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