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.

A233416 c-perfect numbers.

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%I A233416 #28 Jan 29 2019 09:26:51
%S A233416 11,71,226,3676,16911,1143267,4721203,8906035
%N A233416 c-perfect numbers.
%C A233416 A number k is called a c-perfect number if the sum of its proper c-divisors equals k.
%C A233416 For the definition of a c-divisor of an integer, see comment in A124771.
%C A233416 From _Charlie Neder_, Jan 17 2019: (Start)
%C A233416 Sequence in binary: 1011, 1000111, 11100010, 111001011100, 100001000001111, 100010111000111100011, 10010000000101000110011, 100001111110010100110011...
%C A233416 Next term > 10^7. (End)
%H A233416 <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>
%F A233416 A233394(a(n))=2*a(n).
%e A233416 For n=11 which is a concatenation of binary parts (10)(1)(1); we have proper positive c-divisors 1, 2, 3, and 5, the sum of which is 11, so 11 is in the sequence.
%Y A233416 Cf. A124771, A233394.
%K A233416 nonn,more,base
%O A233416 1,1
%A A233416 _Vladimir Shevelev_ and _Peter J. C. Moses_, Dec 09 2013
%E A233416 a(6)-a(8) from _Charlie Neder_, Jan 17 2019