cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A151744 Primes which are the sum of two, three, four and five consecutive composite numbers.

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%I A151744 #15 Apr 16 2015 10:53:11
%S A151744 17783,25057,47303,48383,49297,76343,89783,205703,412343,516457,
%T A151744 704183,754417,790703,938183,1105343,1110743,1279583,1563503,1632817,
%U A151744 1744583,1890743,1903103,2062943,2276303,2714617,2802383,2812897,2932703
%N A151744 Primes which are the sum of two, three, four and five consecutive composite numbers.
%C A151744 17783 is in the list because: 17783 = 8891 + 8892 (sum of two consecutive composite numbers)
%C A151744 17783 = 5926 + 5928 + 5929 (sum of three consecutive composite numbers)
%C A151744 17783 = 4444 + 4445 + 4446 + 4448 (sum of four consecutive composite numbers)
%C A151744 17783 = 3554 + 3555 + 3556 + 3558 + 3560 (sum of five consecutive composite numbers)
%H A151744 Harvey P. Dale, <a href="/A151744/b151744.txt">Table of n, a(n) for n = 1..100</a>
%F A151744 Intersection of A060254, A060328, A060329 and A060330. - _R. J. Mathar_, Jun 17 2009
%t A151744 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 *)
%t A151744 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 *)
%K A151744 nonn
%O A151744 1,1
%A A151744 _Claudio Meller_, Jun 15 2009
%E A151744 Extended beyond a(7) by _Klaus Brockhaus_, Jun 16 2009