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 A151744 Primes which are the sum of two, three, four and five consecutive composite numbers. 3
 17783, 25057, 47303, 48383, 49297, 76343, 89783, 205703, 412343, 516457, 704183, 754417, 790703, 938183, 1105343, 1110743, 1279583, 1563503, 1632817, 1744583, 1890743, 1903103, 2062943, 2276303, 2714617, 2802383, 2812897, 2932703 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS 17783 is in the list because: 17783 = 8891 + 8892 (sum of two consecutive composite numbers) 17783 = 5926 + 5928 + 5929 (sum of three consecutive composite numbers) 17783 = 4444 + 4445 + 4446 + 4448 (sum of four consecutive composite numbers) 17783 = 3554 + 3555 + 3556 + 3558 + 3560 (sum of five consecutive composite numbers) LINKS Harvey P. Dale, Table of n, a(n) for n = 1..100 FORMULA Intersection of A060254, A060328, A060329 and A060330. - R. J. Mathar, Jun 17 2009 MATHEMATICA CompositeNext[n_]:=Module[{k=n+1}, While[PrimeQ[k], k++ ]; k]; q=9!; lst2={}; Do[If[ !PrimeQ[n], c=CompositeNext[n]; a2=n+c; If[PrimeQ[a2], AppendTo[lst2, a2]]], {n, q}]; lst2; lst3={}; Do[If[ !PrimeQ[n], c1=CompositeNext[n]; c2=CompositeNext[c1]; a3=n+c1+c2; If[PrimeQ[a3], AppendTo[lst3, a3]]], {n, q}]; lst3; lst4={}; Do[If[ !PrimeQ[n], c1=CompositeNext[n]; c2=CompositeNext[c1]; c3=CompositeNext[c2]; a4=n+c1+c2+c3; If[PrimeQ[a4], AppendTo[lst4, a4]]], {n, q}]; lst4; lst5={}; Do[If[ !PrimeQ[n], c1=CompositeNext[n]; c2=CompositeNext[c1]; c3=CompositeNext[c2]; c4=CompositeNext[c3]; a5=n+c1+c2+c3+c4; If[PrimeQ[a5], AppendTo[lst5, a5]]], {n, q}]; lst5; Intersection[lst2, lst3, lst4, lst5] (* Vladimir Joseph Stephan Orlovsky, Jun 17 2009 *) Module[{comps=Select[Range[2*10^6], CompositeQ]}, Intersection@@ Table[ Select[ Total/@ Partition[comps, n, 1], PrimeQ], {n, 2, 5}]] (* Harvey P. Dale, Apr 16 2015 *) CROSSREFS Sequence in context: A235023 A133540 A237776 * A250333 A203920 A236649 Adjacent sequences: A151741 A151742 A151743 * A151745 A151746 A151747 KEYWORD nonn AUTHOR Claudio Meller, Jun 15 2009 EXTENSIONS Extended beyond a(7) by Klaus Brockhaus, Jun 16 2009 STATUS approved

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Last modified August 12 12:46 EDT 2024. Contains 375092 sequences. (Running on oeis4.)