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 A163248 Sum of the n-th composite number plus the number of composite numbers less than the n-th noncomposite number. 1
 4, 6, 8, 10, 12, 17, 20, 24, 26, 31, 38, 40, 46, 51, 53, 57, 63, 69, 72, 79, 83, 85, 91, 95, 102, 110, 114, 117, 122, 124, 128, 143, 147, 153, 155, 165, 168, 174, 180, 184, 190, 197, 200, 210, 212, 216, 218, 231, 243, 247 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Bo Gyu Jeong, Table of n, a(n) for n = 1..10000 FORMULA a(n) = A002808(n) + A162177(n) = A008578(n) + A073169(n). MAPLE nnc:= 1: nc:= 0; b[nnc]:= 0:b[0]:= 0: for x from 2 to 1000 do    if isprime(x) then      nnc:= nnc+1; b[nnc]:= b[nnc-1];    else      b[nnc]:= b[nnc]+1;      nc:= nc+1;      c[nc]:= x;    fi od: seq(b[n-1]+c[n], n=1..min(nnc, nc)); # Robert Israel, Jan 09 2015 CROSSREFS Sequence in context: A076298 A194579 A194594 * A034288 A131984 A307542 Adjacent sequences:  A163245 A163246 A163247 * A163249 A163250 A163251 KEYWORD nonn,easy,less AUTHOR Jaroslav Krizek, Jul 23 2009 EXTENSIONS Corrected for Aug 2009 change of offset in A158611 and A008578 by Jaroslav Krizek, Jan 27 2010 STATUS approved

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Last modified May 25 22:17 EDT 2019. Contains 323576 sequences. (Running on oeis4.)