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 A330579 Numbers k such that the k-th composite number divides the sum of the first k composite numbers. 2
 1, 4, 493, 1565, 6210, 26375, 64019, 289862, 870828, 1244485, 3313113, 4300012, 7946206, 1447234860, 4147639664, 7190149312, 23828369695, 39710847388, 494027033160, 982853084580, 1095174951021, 1141650682059, 1522735118076, 1642938906044 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS This sequence corresponds to the positions of zeros in A330578. LINKS EXAMPLE The first 4 composite numbers are: 4, 6, 8 and 9. As 4 + 6 + 8 + 9 = 3*9, 4 belongs to the sequence. PROG (PARI) s=0; k=0; forcomposite (c=4, oo, k++; s+=c; if (s%c==0, print1 (k", "))) CROSSREFS Cf. A024011 (prime variant), A330578, A330580. Sequence in context: A069500 A053953 A024058 * A221554 A210310 A324155 Adjacent sequences:  A330576 A330577 A330578 * A330580 A330581 A330582 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 April 6 14:08 EDT 2020. Contains 333276 sequences. (Running on oeis4.)