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Sum of first n 5-almost primes.
2

%I #7 Jan 19 2018 23:46:55

%S 32,80,152,232,340,452,572,734,902,1078,1258,1458,1666,1909,2161,2425,

%T 2695,2967,3247,3547,3851,4163,4531,4909,5301,5697,6102,6510,6930,

%U 7370,7820,8276,8740,9208,9704,10204,10724,11276,11843,12431,13023,13617

%N Sum of first n 5-almost primes.

%C Elements in this sequence can themselves be 5-almost primes. a(1) = 32 = 2^5. a(2) = 80 = 2^4 * 5. a(27) = 6102 = 2 * 3^3 * 113 a(28) = 6510 = 2 * 3 * 5 * 7 * 31 a(31) = 7820 = 2^2 * 5 * 17 * 23 a(33) = 8740 = 2^2 * 5 * 19 * 23. Does this happen infinitely often? - _Jonathan Vos Post_, Dec 11 2004

%e a(2)=80 because sum of first two 5-almost primes, i.e. 32+48, is 80.

%t Accumulate[Select[Range[1000],PrimeOmega[#]==5&]] (* _Harvey P. Dale_, Jan 19 2018 *)

%K easy,nonn

%O 1,1

%A _Shyam Sunder Gupta_, Aug 24 2003