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.

A018270 Divisors of 70.

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%I A018270 #20 Jul 08 2025 06:34:32
%S A018270 1,2,5,7,10,14,35,70
%N A018270 Divisors of 70.
%C A018270 This number has eight divisors which add up 144. Since that's more than twice 70, the number is abundant. However, 4 is not a divisor, nor can 4 be obtained from the smaller divisors (1 and 2), so there is only one way, the trivial way, to express 70 as a sum of distinct divisors. This is a sharp contrast to most abundant numbers. Hence 70 is a weird number (A006037). - _Alonso del Arte_, Oct 07 2017
%H A018270 <a href="/index/Di#divisors">Index entries for sequences related to divisors of numbers</a>
%t A018270 Divisors[70] (* _Alonso del Arte_, Oct 07 2017 *)
%o A018270 (PARI) divisors(70) \\ _Charles R Greathouse IV_, Jun 21 2017
%K A018270 nonn,fini,full,easy
%O A018270 1,2
%A A018270 _N. J. A. Sloane_