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 A108423 a(n) = A108422(n) - A108421(n). 3
 0, 0, 0, 1, 0, 1, 0, 1, 2, 2, 1, 0, 1, 2, 0, 3, 2, 2, 2, 3, 3, 3, 1, 2, 2, 4, 1, 3, 3, 3, 0, 1, 0, 4, 3, 3, 4, 5, 2, 3, 4, 2, 3, 5, 4, 4, 1, 0, 4, 4, 3, 4, 4, 4, 2, 4, 2, 4, 3, 2, 1, 3, 0, 3, 2, 5, 4, 4, 5, 4, 3, 4, 4, 5, 3, 5, 5, 5, 2, 3, 4, 4, 4, 5, 3, 6, 1, 3, 5, 3, 1, 5, 4, 2, 1, 4, 4, 6, 4, 4, 4, 6, 2, 6, 4 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,9 COMMENTS a(A000079(n)) = 0. LINKS Robert Israel, Table of n, a(n) for n = 2..10000 MAPLE N:= 200: # to get a(2)..a(N) Primes:= select(isprime, [seq(i, i=3..2*N-3, 2)]): Ones:= map(t -> convert(convert(t, base, 2), `+`), Primes): VL:= Vector(N): VL[2]:= 2: VH:= Vector(N): VH[2]:= 2: for i from 1 to nops(Primes) do   p:= Primes[i];   for j from 1 to i do     k:= (p+Primes[j])/2;     if k > N then break fi;     t:= Ones[i]+Ones[j];     if t > VH[k] then VH[k]:= t fi;     if VL[k]=0 or t < VL[k] then VL[k]:= t fi;   od od: convert((VH-VL)[2..N], list); # Robert Israel, Mar 26 2018 CROSSREFS Sequence in context: A226289 A107063 A290453 * A208568 A193804 A180424 Adjacent sequences:  A108420 A108421 A108422 * A108424 A108425 A108426 KEYWORD nonn,base AUTHOR Reinhard Zumkeller, Jun 03 2005 STATUS approved

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Last modified May 13 14:25 EDT 2021. Contains 343859 sequences. (Running on oeis4.)