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%I #12 Feb 08 2014 01:55:49
%S 16,40,76,116,170,226,286,367,451,539,629,729,833,959,1091,1226,1362,
%T 1502,1652,1804,1960,2144,2333,2529,2727,2931,3141,3361,3586,3814,
%U 4046,4280,4528,4778,5038,5314,5608,5904,6201,6507,6815,7130,7458,7788,8128
%N Sum of first n 4-almost primes.
%C Elements in this sequence can themselves be 4-almost primes. a(1) = 16 = 2^4. a(2) = 40 = 2^3 * 5. a(19) = 1652 = 2^2 * 7 * 59. a(20) = 1804 = 2^2 * 11 * 41. a(31) = 4046 = 2 * 7 * 17^2. a(37) = 5608 = 2^3 * 701. a(39) = 6201 = 3^2 * 13 * 53. a(40) = 6507 = 3^3 * 241. a(42) = 7130 = 2 * 5 * 23 * 31. a(43) = 7458 = 2 * 3 * 11 * 113. Does this happen infinitely often? - _Jonathan Vos Post_, Dec 11 2004
%H Vincenzo Librandi, <a href="/A086046/b086046.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = sum_{i=1..n} A014613(i). - _R. J. Mathar_, Sep 14 2012
%e a(2)=40 because sum of first two 4-almost primes i.e. 16+24 is 40.
%t Accumulate[Select[Range[1000],PrimeOmega[#]==4&]] (* _Harvey P. Dale_, Feb 07 2014 *)
%K easy,nonn
%O 1,1
%A _Shyam Sunder Gupta_, Aug 24 2003
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