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A362420
Partial sum of the first n odd semiprimes.
2
9, 24, 45, 70, 103, 138, 177, 226, 277, 332, 389, 454, 523, 600, 685, 772, 863, 956, 1051, 1162, 1277, 1396, 1517, 1640, 1769, 1902, 2043, 2186, 2331, 2486, 2645, 2806, 2975, 3152, 3335, 3520, 3707, 3908, 4111, 4316
OFFSET
1,1
COMMENTS
The numbers 62234 and 199370 are in this sequence and also in A362419. - Zak Seidov and Robert Israel, Apr 10 2023
FORMULA
a(n) = Sum_{i=1..n} A046315(i).
MAPLE
A362420 := proc(n)
option remember ;
if n = 0 then
0 ;
else
procname(n-1)+A046315(n) ;
end if;
end proc:
seq(A362420(n), n=1..40) ;
MATHEMATICA
Accumulate[Select[Range[1, 250, 2], PrimeOmega[#] == 2 &]] (* Paolo Xausa, Mar 19 2024 *)
CROSSREFS
Sequence in context: A161449 A063066 A262044 * A097658 A067725 A213903
KEYWORD
nonn,easy
AUTHOR
R. J. Mathar, Apr 19 2023
STATUS
approved