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A018270 Divisors of 70. 1
1, 2, 5, 7, 10, 14, 35, 70 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

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

LINKS

Table of n, a(n) for n=1..8.

Index entries for sequences related to divisors of numbers

MATHEMATICA

Divisors[70] (* Alonso del Arte, Oct 07 2017 *)

PROG

(PARI) divisors(70) \\ Charles R Greathouse IV, Jun 21 2017

CROSSREFS

Sequence in context: A276465 A018406 A018483 * A080180 A159942 A102339

Adjacent sequences:  A018267 A018268 A018269 * A018271 A018272 A018273

KEYWORD

nonn,fini,full,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified November 20 15:02 EST 2018. Contains 317402 sequences. (Running on oeis4.)