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A086061
Sum of first n 8-almost primes.
1
256, 640, 1216, 1856, 2720, 3616, 4576, 5872, 7216, 8624, 10064, 11664, 13328, 15272, 17288, 19400, 21560, 23736, 25976, 28376, 30808, 33304, 36220, 39164, 42188, 45324, 48492, 51732, 54996, 58356, 61876, 65476, 69124, 72836, 76580
OFFSET
1,1
COMMENTS
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
LINKS
EXAMPLE
a(2)=640 because sum of first two 8-almost primes i.e. 256+384 is 640.
MATHEMATICA
Accumulate[Select[Range[10000], Total[FactorInteger[#][[;; , 2]]]==8&]] (* Harvey P. Dale, Nov 02 2024 *)
CROSSREFS
Sequence in context: A134609 A260065 A329488 * A235092 A237015 A237008
KEYWORD
easy,nonn,changed
AUTHOR
Shyam Sunder Gupta, Aug 24 2003
STATUS
approved