|
%I #18 Sep 25 2015 14:21:47
%S 0,4,6,12,18,27,30,42,45,60,63,72,102,108,117,130,135,138,150,170,180,
%T 192,198,207,228,240,243,250,270,280,282,297,312,315,320,333,348,380,
%U 387,420,430,432,462,495,522,570,585,600,618,642,651,660,670,675,693
%N Sums of the composite numbers placed between two consecutive prime numbers (A054265), sorted in increasing order.
%C The first number that occurs more than once is 2592 = a(143) = a(144). - _Robert Israel_, Nov 11 2014
%H Robert Israel, <a href="/A249630/b249630.txt">Table of n, a(n) for n = 1..10000</a>
%p N:= 1000: # to get all terms <= N
%p Primes:= select(isprime,[2,seq(2*i+1,i=1..floor(N/2))]):
%p B:= [seq((Primes[i+1]+Primes[i])*(Primes[i+1]-Primes[i]-1)/2, i=1..nops(Primes)-1)]:
%p sort(select(`<=`,B,N)); # _Robert Israel_, Nov 11 2014
%t With[{nn=60},Take[Sort[Total[Range[#[[1]]+1,#[[2]]-1]]&/@Partition[ Prime[ Range[3*nn]],2,1]],nn]] (* _Harvey P. Dale_, Sep 25 2015 *)
%o (PARI) lista() = {vitp = readvec("c:/gp/bfiles/b029707.txt"); for (k=1, #vitp, v = []; for (n=1, k, vn = vitp[n]; for (j=1, vn, newv = (prime(j+1)+prime(j))*(prime(j+1)-prime(j)-1)/2; if (! vecsearch(v, newv), v = vecsort(concat(v, newv)));););/* to see intermediate results for (i=1, #v, if (v[i] <= newv, print1(v[i], ", "));); print();*/); v;} \\ _Michel Marcus_, Nov 11 2014
%Y Cf. A054265.
%K nonn
%O 1,2
%A _Yves Debeuret_, Nov 02 2014
%E More terms from _Michel Marcus_, Nov 11 2014
|
