

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
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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(ni)[2]; c:=(ni)*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, A211223A211225, 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



