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%I #11 Mar 01 2023 15:32:36
%S 1,3,5,7,9,11,22,33,44,55,22,33,44,55,66,33,44,55,66,77,44,55,66,77,
%T 88,55,66,77,88,99,111,212,313,414,515,131,232,333,434,535,151,252,
%U 353,454,555,171,272,373,474,575,191,292,393,494,595,212,313,414,515,616
%N Arithmetic mean of k and R(k) where k is a number using all odd digits and R(k) is its digit reversal (A004086).
%F {k + R(k)}/2 where k uses only odd digits 1, 3, 5, 7 and 9.
%p reversal := proc(n) local i, len, new, temp: new := 0: temp := n: len := floor(log[10](n+.1))+1: for i from 1 to len do new := new+irem(temp, 10)*10^(len-i): temp := floor(temp/10): od: RETURN(new): end: allodd := proc(n) local i, flag, len, temp: temp := n: flag := 1: if n=0 then flag := 0 fi: len := floor(log[10](n+.1))+1: for i from 1 to len do if irem(temp, 10) mod 2 = 1 then temp := floor(temp/10) else flag := 0 fi: od: RETURN(flag): end: for n from 1 to 501 by 2 do if allodd(n) = 1 then printf(`%d,`,(n+reversal(n))/2) fi: od: # _James A. Sellers_, May 28 2002
%Y Cf. A004086, A071241, A071242.
%K base,nonn
%O 0,2
%A _Amarnath Murthy_, May 20 2002
%E More terms from _James A. Sellers_, May 28 2002
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