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 A323069 Number of divisors d of n such that A049820(d) > 1 and A049820(d) is also a divisor of n. 3
 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 2, 0, 0, 1, 1, 0, 2, 0, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 3, 0, 1, 0, 0, 1, 4, 0, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 4, 0, 0, 0, 0, 0, 2, 0, 1, 0, 0, 0, 4, 0, 0, 0, 1, 0, 1, 0, 0, 0, 2, 0, 5, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 0, 2, 0, 0, 0, 1, 0, 4, 0, 0, 0, 0, 0, 4, 0, 0, 1, 0, 0, 1, 0, 1, 2 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,12 LINKS Antti Karttunen, Table of n, a(n) for n = 1..10080 FORMULA Sum_{d|n} [A049820(d) > 1 and A049820(d)|n], where [ ] is the Iverson bracket. a(n) <= A323068(n). a(n) >= A322358(n). PROG (PARI) A323069(n) = sumdiv(n, d, my(t=(d-numdiv(d))); ((t>1)&&!(n%t))); CROSSREFS Cf. A000005, A049820, A322358, A323068. Sequence in context: A161369 A151843 A276422 * A325334 A280287 A147696 Adjacent sequences:  A323066 A323067 A323068 * A323070 A323071 A323072 KEYWORD nonn AUTHOR Antti Karttunen, Jan 05 2019 STATUS approved

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Last modified September 27 12:30 EDT 2020. Contains 337380 sequences. (Running on oeis4.)