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Sum of the reversals of the divisors of n.
7

%I #18 Feb 10 2017 21:09:31

%S 1,3,4,7,6,12,8,15,13,9,12,37,32,51,60,76,72,102,92,15,23,36,33,87,58,

%T 96,85,137,93,72,14,99,48,117,66,190,74,177,128,27,15,96,35,84,123,99,

%U 75,232,102,66,90,125,36,219,72,210,170,180,96,105,17,42,68,145,93,144,77,207,132,117,18,267,38,123,169,248

%N Sum of the reversals of the divisors of n.

%H Indranil Ghosh, <a href="/A069192/b069192.txt">Table of n, a(n) for n = 1..50000</a>

%H Pe, J. <a href="http://www.numeratus.net/enlightened/pictureperfect.html">The Picture-Perfect Numbers</a>

%e The divisors of 10 are 1,2,5,10, which reversed are 1,2,5,1, summing to 9. Therefore a(10) = 9.

%p read("transforms") ;

%p A069192 := proc(n)

%p add(digrev(d),d=numtheory[divisors](n)) ;

%p end proc: # _R. J. Mathar_, Sep 09 2015

%t f[n_] := FromDigits[Reverse[IntegerDigits[n]]]; g[n_] := Apply[Plus, Map[f, Divisors[n]]]; Table[g[i], {i, 1, 40}]

%o (Python)

%o def A069192(n):

%o ....s=0

%o ....for i in range(1,n+1):

%o ........if n%i==0: s+=int(str(i)[::-1])

%o ....return s # _Indranil Ghosh_, Feb 10 2017

%Y Cf. A000203, A069250.

%K base,nonn

%O 1,2

%A _Joseph L. Pe_, Apr 19 2002

%E Added more terms, corrected offset. - _N. J. A. Sloane_, May 19 2013