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A273993
Numbers whose derivative is equal to the arithmetic derivative.
2
0, 1, 2, 10, 22, 34, 38, 46, 94, 134, 142, 158, 262, 382, 514, 526, 542, 766, 2062, 2078, 2174, 2302, 2558, 4126, 4222, 7871, 8198, 8222, 8254, 8318, 10238, 12286, 16894, 32894, 40958, 65542, 65566, 65662, 66046, 67582, 131074, 131078, 131086, 131102, 131198, 132094
OFFSET
1,3
LINKS
FORMULA
Solution of the equation A003415(n) = A038554(n).
EXAMPLE
10 in base 2 is 1010 and its derivative is (1+0)(0+1)(1+0)-> 111 that is 7 in base 10 and 7 is also the arithmetic derivative of 10.
MAPLE
with(numtheory): P:=proc(q) local a, b, i, n, p;
for n from 0 to q do a:=0; b:=convert(n, base, 2);
for i from 1 to nops(b)-1 do a:=a+((b[i]+b[i+1]) mod 2)*2^(i-1); od;
if a=n*add(op(2, p)/op(1, p), p=ifactors(n)[2]) then print(n); fi;
od; end: P(10^6);
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Paolo P. Lava, Jun 08 2016
STATUS
approved