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A086061 Sum of first n 8-almost primes. 0

%I

%S 256,640,1216,1856,2720,3616,4576,5872,7216,8624,10064,11664,13328,

%T 15272,17288,19400,21560,23736,25976,28376,30808,33304,36220,39164,

%U 42188,45324,48492,51732,54996,58356,61876,65476,69124,72836,76580

%N Sum of first n 8-almost primes.

%C Elements in this sequence can themselves be 8-almost primes, as happens often for 5-almost primes. a(1) = 256 = 2^8. Also an 8-Brilliant number. a(2) = 640 = 2^7 * 5. Also an 8-Brilliant number. Does this happen infinitely often? - _Jonathan Vos Post_, Dec 11 2004

%e a(2)=640 because sum of first two 8-almost primes i.e. 256+384 is 640.

%K easy,nonn

%O 1,1

%A _Shyam Sunder Gupta_, Aug 24 2003

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Last modified February 1 12:28 EST 2023. Contains 359993 sequences. (Running on oeis4.)