A244251 Numbers k such that if m = (sum of the reverses of the aliquot parts of k) then k = (sum of the reverses of the aliquot parts of m).

6, 98, 145, 244, 285, 133857

Offset

1,1

Comments

A072228 is a subsequence of this sequence.

Links

Table of n, a(n) for n=1..6.

Example

Aliquot parts of 98 are 1, 2, 7, 14, 49 and the sum of their reverses is 1 + 2 + 7 + 41 + 94 = 145. Aliquot parts of 145 are 1, 5, 29 and the sum of their reverses is 1 + 5 + 92 = 98.

Maple

with(numtheory): T:=proc(w) local x, y, z; x:=0; y:=w;
for z from 1 to ilog10(w)+1 do x:=10*x+(y mod 10); y:=trunc(y/10); od; x; end:
P:=proc(q) local a, b, k, n; for n from 1 to q do
a:=sort([op(divisors(n))]); b:=add(T(a[k]), k=1..nops(a)-1); a:=sort([op(divisors(b))]); b:=add(T(a[k]), k=1..nops(a)-1);
if b=n then print(n); fi; od; end: P(10^12);

Crossrefs

Cf. A072228.

Sequence in context: A288544 A064753 A322739 * A187522 A224615 A138913

Adjacent sequences: A244248 A244249 A244250 * A244252 A244253 A244254

Keyword

nonn,more,base

Author

Paolo P. Lava, Dec 09 2014

Status

approved