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 A213020 Smallest number k such that the sum of prime factors of k (counted with multiplicity) is n times a prime. 2
 2, 4, 8, 15, 21, 35, 33, 39, 65, 51, 57, 95, 69, 115, 86, 87, 93, 155, 212, 111, 122, 123, 129, 215, 141, 235, 158, 159, 265, 371, 177, 183, 194, 427, 201, 335, 213, 219, 365, 511, 237, 395, 249, 415, 446, 267, 278, 623, 964, 291, 302, 303, 309, 515, 321, 327 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Smallest k such that sopfr(k) = n*p, p prime. LINKS Alois P. Heinz, Table of n, a(n) for n = 1..5000 EXAMPLE a(19) = 212 because 212 = 2^2 * 53 => sum of prime factors = 2*2+53 = 57 = 19*3 where 3 is prime. MAPLE sopfr:= proc(n) option remember;           add(i[1]*i[2], i=ifactors(n)[2])         end: a:= proc(n) local k, p;       for k from 2 while irem (sopfr(k), n, 'p')>0 or         not isprime(p) do od; k     end: seq (a(n), n=1..100); # Alois P. Heinz, Jun 03 2012 CROSSREFS Cf. A001414, A100118, A213015, A213016. Sequence in context: A287163 A290652 A288313 * A279858 A026474 A301629 Adjacent sequences:  A213017 A213018 A213019 * A213021 A213022 A213023 KEYWORD nonn AUTHOR Michel Lagneau, Jun 02 2012 STATUS approved

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Last modified July 19 08:33 EDT 2019. Contains 325155 sequences. (Running on oeis4.)