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A278948 Numbers such that the sum of the reverse of their aliquot parts is equal to the reverse of the sum of their aliquot parts. 0
4, 6, 8, 9, 10, 15, 21, 25, 49, 1261, 2449, 2701, 2881, 3006, 7486, 9265, 21583, 21809, 22663, 22987, 23707, 23711, 24257, 24613, 24797, 25021, 25217, 25283, 25807, 26123, 26167, 27331, 28199, 28417, 28841, 29143, 29503, 29747, 29987, 30227, 31133, 31313, 31459 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..43.

EXAMPLE

Aliquot parts of 3006 are 1, 2, 3, 6, 9, 18, 167, 334, 501, 1002, 1503. The sum of their reverse is 1 + 2 + 3 + 6 + 9 + 81 + 761 + 433 + 105 + 2001 + 3051 = 6453. The sum of aliquot parts is sigma(3006) - 3006 = 3546 whose reverse is 6453.

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, c, k, n; for n from 1 to q do if not isprime(n) then

c:=0; a:=sort([op(divisors(n))]); for k from 1 to nops(a)-1 do c:=c+T(a[k]); od;

if T(sigma(n)-n)=c then print(n); fi; fi; od; end: P(10^9);

CROSSREFS

Cf. A001065, A203605.

Sequence in context: A062115 A141613 A072362 * A084988 A202265 A004716

Adjacent sequences:  A278945 A278946 A278947 * A278949 A278950 A278951

KEYWORD

nonn,base,easy

AUTHOR

Paolo P. Lava, Dec 02 2016

STATUS

approved

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Last modified October 22 01:46 EDT 2020. Contains 337948 sequences. (Running on oeis4.)