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A254008
Numbers that divide the sum of the reverse of their divisors (A069192).
2
1, 6, 15, 37, 87, 397, 435, 639, 1086, 2574, 8997, 10986, 26994, 101918, 161406, 207321, 793170, 834657, 890827, 1976355, 3224625, 7591023, 8999997, 9970098, 11052598, 17930619, 18368601, 21739023, 38014197, 89999997, 109999986, 116141652, 177765554, 201264120
OFFSET
1,2
LINKS
EXAMPLE
Divisors of 8997 are 1, 3, 2999, 8997 and the sum of their reverse is 1 + 3 + 9992 + 7998 = 17994. Finally, 17994 / 8997 = 2.
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, k; global n;
for n from 1 to q do a:=sort([op(divisors(n))]); b:=add(T(a[k]), k=1..nops(a));
if type(b/n, integer) then print(n); fi; od; end: P(10^9);
PROG
(Magma) [n: n in [1..10^6] | &+[Seqint(Reverse(Intseq(d))): d in Divisors(n)] mod n eq 0]; // Bruno Berselli, Jan 22 2015
CROSSREFS
Sequence in context: A221905 A083011 A299267 * A277089 A271545 A272258
KEYWORD
nonn,base
AUTHOR
Paolo P. Lava, Jan 22 2015
EXTENSIONS
a(19)-a(33) from Lars Blomberg, Feb 27 2015
STATUS
approved