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%I #6 Mar 07 2023 10:41:45
%S 1,4,9,16,25,36,49,64,81,1,4,9,16,25,36,49,64,81,10,4,9,16,25,36,49,
%T 64,81,10,121,9,16,25,36,49,64,81,10,121,252,16,25,36,49,64,81,10,121,
%U 252,403,25,36,49,64,81,10,121,252,403,574,36,49,64,81,10,121,252,403,574
%N Sum of digits of n, times digital reversal of sum of digits of n.
%C The fixed points of this sequence {n such that a(n) = n} are A110921.
%H Harvey P. Dale, <a href="/A153211/b153211.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = SOD(n)*R(SOD(n)) = A007953(n)*A004086(A007953(n)).
%e a(19) = (1+9)*R(1+9) = 10*01 = 10*1 = 10. a(79) = 976 because (7+9)*R(7+9) = 16*61 = 976.
%t Table[With[{ds=Total[IntegerDigits[n]]},IntegerReverse[ds]ds],{n,70}] (* _Harvey P. Dale_, Mar 07 2023 *)
%Y Cf. A004086, A007953, A110921.
%K base,easy,nonn
%O 1,2
%A _Jonathan Vos Post_, Dec 20 2008
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