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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Lars Blomberg, Table of n, a(n) for n = 1..41

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

Cf. A069192, A254009.

Sequence in context: A221905 A083011 A299267 * A277089 A271545 A272258

Adjacent sequences:  A254005 A254006 A254007 * A254009 A254010 A254011

KEYWORD

nonn,base

AUTHOR

Paolo P. Lava, Jan 22 2015

EXTENSIONS

a(19)-a(33) from Lars Blomberg, Feb 27 2015

STATUS

approved

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Last modified February 19 09:19 EST 2018. Contains 299330 sequences. (Running on oeis4.)