A259077 Non-palindromic composite numbers such that n' = [Rev(n)]', where n' is the arithmetic derivative of n.

366, 663, 3245, 3685, 5423, 5863, 8178, 8718, 14269, 15167, 16237, 18449, 18977, 36679, 73261, 76151, 77981, 94481, 96241, 97663, 140941, 149041, 150251, 152051, 196891, 198691, 302363, 308459, 319853, 335148, 358913, 363203, 841533, 921239, 932129, 954803, 958099, 990859

Offset

1,1

Links

Table of n, a(n) for n=1..38.

Formula

Solutions to A003415(n) = A003415(A004086(n)), with A004086(n) <> n.

Example

366' = 311 = 663';
3245' = 999 = 5423'; etc.

Maple

with(numtheory): T:=proc(w) local x, y, z; x:=w; y:=0;
for z from 1 to ilog10(x)+1 do y:=10*y+(x mod 10); x:=trunc(x/10);
od; y; end: P:=proc(q) local a, b, p, n;
for n from 1 to q do if not isprime(n) then if n<>T(n) then a:=n*add(op(2, p)/op(1, p), p=ifactors(n)[2]);
b:=T(n)*add(op(2, p)/op(1, p), p=ifactors(T(n))[2]);
if a=b then print(n); fi; fi; fi; od; end: P(10^9);

Crossrefs

Cf. A003415, A004086, A085329, A097647.

Sequence in context: A258485 A073305 A248552 * A219960 A033174 A350471

Adjacent sequences: A259074 A259075 A259076 * A259078 A259079 A259080

Keyword

nonn,base

Author

Paolo P. Lava, Jun 18 2015

Status

approved