A250067 - OEIS

A250067

Numbers n such that n = Rev(sigma*(n)), where sigma*(n) is the sum of the anti-divisors of n and Rev(n) is the reverse of n.

5, 8, 64, 614, 47678, 4442395

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OFFSET

1,1

LINKS

EXAMPLE

Anti-divisors of 5 are 2, 3 and 2 + 3 = 5 = Rev(5).

Anti-divisors of 614 are 3, 4, 409 and 3 + 4 + 409 = 416 = Rev(614).

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 j, k, n; for n from 1 to q do

k:=0; j:=n; while j mod 2 <> 1 do k:=k+1; j:=j/2; od;

if sigma(2*n+1)+sigma(2*n-1)+sigma(n/2^k)*2^(k+1)-6*n-2=T(n);

then print(n); fi; od; end: P(10^9);

CROSSREFS

KEYWORD

nonn,base,more

AUTHOR

EXTENSIONS

a(6) from Chai Wah Wu, Dec 06 2014

STATUS

approved