cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A086062 Sum of first n 3-almost primes.

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%I A086062 #9 Jan 17 2014 17:37:20
%S A086062 8,20,38,58,85,113,143,185,229,274,324,376,439,505,573,643,718,794,
%T A086062 872,964,1062,1161,1263,1368,1478,1592,1708,1825,1949,2074,2204,2342,
%U A086062 2489,2637,2790,2944,3108,3273,3443,3614,3786,3960,4135,4317,4503,4691,4881
%N A086062 Sum of first n 3-almost primes.
%C A086062 Elements in this sequence can themselves be 3-almost primes. a(1) = 8 = 2^3. a(2) = 20 = 2^2 * 5. a(20) = 964 = 2^2 * 241. a(28) = 1825 = 5^2 * 73. a(30) = 2074 = 2 * 17 * 61. a(34) = 2637 = 3^2 * 293. a(40) = 3614 = 2 * 13 * 139. a(41) = 3786 = 2 * 3 * 631. a(45) = 4503 = 3 * 19 * 79. Does this happen infinitely often? - _Jonathan Vos Post_, Dec 11 2004
%H A086062 Harvey P. Dale, <a href="/A086062/b086062.txt">Table of n, a(n) for n = 1..1000</a>
%F A086062 a(n) = sum_{i=1..n} A014612(i). - _R. J. Mathar_, Sep 14 2012
%e A086062 a(2)=20 because sum of first two 3-almost primes i.e. 8+12 is 20.
%t A086062 Accumulate[Select[Range[500],PrimeOmega[#]==3&]] (* _Harvey P. Dale_, Jan 17 2014 *)
%K A086062 easy,nonn
%O A086062 1,1
%A A086062 _Shyam Sunder Gupta_, Aug 24 2003