cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A152088 Positive integers k that when written in binary have exactly the same number of (non-leading) 0's as the number of divisors of k.

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%I A152088 #14 Dec 28 2019 07:48:22
%S A152088 19,33,34,43,49,53,69,74,79,82,103,107,109,141,142,166,177,178,201,
%T A152088 202,209,226,261,268,292,295,299,301,302,309,314,327,334,339,341,346,
%U A152088 355,358,362,367,379,388,391,395,398,403,422,431,439,443,451,453,454,458
%N A152088 Positive integers k that when written in binary have exactly the same number of (non-leading) 0's as the number of divisors of k.
%H A152088 Amiram Eldar, <a href="/A152088/b152088.txt">Table of n, a(n) for n = 1..10000</a>
%e A152088 34 written in binary is 100010, which has four 0's. Also, 34 has 4 divisors (1,2,17,34). Since the number of binary 0's equals the number of divisors, then 34 is included in this sequence.
%t A152088 Select[Range[500], DigitCount[#, 2, 0] == DivisorSigma[0, #] &] (* _Amiram Eldar_, Dec 28 2019 *)
%Y A152088 Cf. A000005, A023416, A071593, A080791.
%K A152088 nonn,base
%O A152088 1,1
%A A152088 _Leroy Quet_, Nov 23 2008
%E A152088 Extended by _Ray Chandler_, Nov 26 2008