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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: A016380 A341354 A203945 * A341774 A015692 A016232

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 March 8 13:59 EST 2021. Contains 341949 sequences. (Running on oeis4.)