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 A283873 Smallest number that is the sum of n successive primes and also the sum of n successive semiprimes, n > 1. 2
 24, 749, 48, 311, 690, 251, 2706, 2773, 6504, 1081, 2162, 1753, 11356, 6223, 1392, 2303, 9838, 637, 14510, 1995, 3154, 21459, 72960, 5691, 8140, 1475, 2350, 3647, 1593, 7607, 55074, 2719, 9852, 12143, 106562, 12615, 9036, 19883, 15438, 28369, 8560, 8415, 3831 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,1 COMMENTS The sequence is non-monotone. LINKS Alois P. Heinz, Table of n, a(n) for n = 2..1000 EXAMPLE a(2) = 24 = A000040(5) + A000040(6) = 11 + 13 = A001358(4) + A001358(5) = 10 + 14, a(3) = 749 = A000040(53) + A000040(54) + A000040(55) = 241 + 251 + 257 = A001358(79) + A001358(80) + A001358(81) = 247 + 249 + 253. MAPLE issp:= n-> is(not isprime(n) and numtheory[bigomega](n)=2): ithsp:= proc(n) option remember; local k; for k from 1+         `if`(n=1, 1, ithsp(n-1)) while not issp(k) do od; k         end: ps:= proc(i, j) option remember;        ithprime(j)+`if`(i=j, 0, ps(i, j-1))      end: ss:= proc(i, j) option remember;        ithsp(j)+`if`(i=j, 0, ss(i, j-1))      end: a:= proc(n) option remember; local i, j, k, l, p, s;       i, j, k, l, p, s:= 1, n, 1, n, ps(1, n), ss(1, n);       do if p=s then return p        elif p

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Last modified January 16 23:44 EST 2019. Contains 319206 sequences. (Running on oeis4.)