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 A212663 Number of ways to represent n’ as x’ + y’, where x+y = n, x > 0, and n’, x’, y’ are the arithmetic derivatives of n, x, y. 4
 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 2, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 2, 0, 0, 2, 0, 0, 1, 1, 0, 1, 2, 0, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,39 LINKS Paolo P. Lava, Table of n, a(n) for n = 1..5000 MAPLE with(numtheory); A212663:=proc(q) local a, b, c, i, n, p, pfs, t; for n from 1 to q do   pfs:=ifactors(n)[2]; a:=n*add(op(2, p)/op(1, p), p=pfs); t:=0;   for i from 1 to trunc(n/2) do    pfs:=ifactors(i)[2]; b:=i*add(op(2, p)/op(1, p), p=pfs);    pfs:=ifactors(n-i)[2]; c:=(n-i)*add(op(2, p)/op(1, p), p=pfs);    if a=b+c then t:=t+1; fi;   od;   print(t); od; end: A212663(1000); CROSSREFS Cf. A003415, A211223-A211225, A212662, A212664. Sequence in context: A242192 A016380 A203945 * A015692 A016232 A007949 Adjacent sequences:  A212660 A212661 A212662 * A212664 A212665 A212666 KEYWORD nonn AUTHOR Paolo P. Lava, May 23 2012 STATUS approved

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Last modified December 6 14:15 EST 2019. Contains 329806 sequences. (Running on oeis4.)