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A330580 Composite numbers n that divide the sum of all composite numbers <= n. 1
4, 9, 604, 1849, 7123, 29588, 71056, 317238, 945414, 1347895, 3567705, 4624025, 8518502, 1523051853, 4353560959, 7537630621, 24916885136, 41483524658, 513849020166, 1021228997529, 1137756574012, 1185967711155, 1581191501535, 1705826324526 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..24.

FORMULA

a(n) = A002808(A330579(n)).

PROG

(PARI) s=0; k=0; forcomposite (c=4, oo, k++; s+=c; if (s%c==0, print1 (c", ")))

CROSSREFS

Cf. A002808, A007506 (prime variant), A330579.

Sequence in context: A068708 A063248 A027522 * A254959 A028869 A179935

Adjacent sequences:  A330577 A330578 A330579 * A330581 A330582 A330583

KEYWORD

nonn,more

AUTHOR

Rémy Sigrist, Dec 18 2019

EXTENSIONS

a(15)-a(24) from Giovanni Resta, Dec 20 2019

STATUS

approved

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Last modified December 3 12:16 EST 2021. Contains 349462 sequences. (Running on oeis4.)