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A056763 Number of x integers between 2^(n-1) and 2^n for which d(x)^3 > x holds, i.e., cube of number of divisors of x exceeds the number x and binary size of x is n. 0

%I #12 May 06 2022 16:11:15

%S 1,2,4,6,11,24,30,60,110,137,248,399,491,801,1146,1386,1988,2525,2914,

%T 3637,4081,4334,4649,4579,4305,3867,3211,2467,1730,1119,592,272

%N Number of x integers between 2^(n-1) and 2^n for which d(x)^3 > x holds, i.e., cube of number of divisors of x exceeds the number x and binary size of x is n.

%e a(5)=11 because 11 integers occur between 1 + 2^4 = 17 and 2^ 5=32 for which the cube of number of divisors exceeds the number itself: {18,20,21,22,24,25,26,27,28,30,32} Between 2^28 and 2^29, 1730 such numbers occur.

%Y Cf. A000005, A029837, A034884, A035033-A035035, A056757-A056767.

%K nonn,more

%O 1,2

%A _Labos Elemer_, Aug 16 2000

%E a(30)-a(32) from _Sean A. Irvine_, May 06 2022

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Last modified April 19 05:19 EDT 2024. Contains 371782 sequences. (Running on oeis4.)