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 A259643 Numbers n such that sum of first n odd primes divides product of first n odd primes. 1
 1, 3, 5, 11, 25, 29, 41, 49, 51, 59, 69, 81, 99, 103, 113, 131, 133, 135, 147, 149, 153, 181, 187, 193, 197, 199, 205, 211, 213, 217, 219, 229, 235, 239, 243, 255, 271, 277, 281, 287, 289, 303, 309, 313, 323, 333, 335, 343, 347, 357, 359, 365, 367, 381, 383, 389 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Obviously, a(n) is always an odd number. LINKS EXAMPLE a(1) = 1 because prime(2) mod prime(2) = 3 mod 3 = 0. a(2) = 3 because (prime(2) * prime(3) * prime(4)) mod (prime(2) + prime(3) + prime(4)) = 105 mod 15 = 0. a(3) = 5 because (prime(2) * prime(3) * prime(4) * prime(5) * prime(6)) mod (prime(2) + prime(3) + prime(4) + prime(5) + prime(6)) = 15015 mod 39 = 0. PROG for(n=1, 1e3, if( prod(k=1, n, prime(k+1)) % sum(k=1, n, prime(k+1)) == 0 , print1(n", "))) CROSSREFS Cf. A051838, A065091, A070826, A071089, A071148, A262807. Sequence in context: A214873 A330951 A018116 * A167796 A261896 A285184 Adjacent sequences:  A259640 A259641 A259642 * A259644 A259645 A259646 KEYWORD nonn,easy AUTHOR Altug Alkan, Oct 02 2015 STATUS approved

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Last modified December 4 13:29 EST 2021. Contains 349526 sequences. (Running on oeis4.)