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 A093552 a(n) is the smallest number m such that m-k is product of k+1 primes for k=0,1,2,...,n. 6
 2, 5, 47, 107, 71999, 392279, 305778479, 24405534719, 899133243623 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS Each term of this sequence is prime. LINKS EXAMPLE a(5)=392279 because: 392279 is prime; 392279-1 = 2*196139; 392279-2 = 3*229*571; 392279-3 = 2*2*281*349; 392279-4 = 5*5*13*17*71; 392279-5 = 2*3*3*19*31*37; 392279 is the smallest number m such that m-k is product of k+1 primes for k=0,1,2,3,4 & 5. MATHEMATICA Table[m = 1; While[Table[Plus @@ Last /@ FactorInteger[Prime[m] - k], {k, 0, n}] != Range[1, n + 1], m++]; Prime[m], {n, 0, 5}] (* Robert Price, Jun 09 2019 *) CROSSREFS Cf. A072664, A072875, A086560. Sequence in context: A041729 A078665 A163666 * A060808 A099658 A244014 Adjacent sequences:  A093549 A093550 A093551 * A093553 A093554 A093555 KEYWORD nonn,more AUTHOR Farideh Firoozbakht, Apr 14 2004 EXTENSIONS a(6) corrected by Mike Oakes, Jun 20 2012 a(7) from Zak Seidov, Apr 23 2017 a(8) from Giovanni Resta, Apr 27 2017 STATUS approved

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Last modified August 22 11:34 EDT 2019. Contains 326176 sequences. (Running on oeis4.)