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A115336 a(n) is the smallest number representable in exactly n ways as a sum of 2 palindromes (each of them >= 0). 2

%I #3 Mar 30 2012 17:40:34

%S 0,2,4,6,8,110,353,363,373,383,393,464,474,504,484,494,575,605,585,

%T 1049,595,767,706,686,777,696,807,787,878,13222,797,908,888,31812,

%U 12892,898,989,11220,44444,1201,999,28882,11110,42623,30092,1100,11000,36153

%N a(n) is the smallest number representable in exactly n ways as a sum of 2 palindromes (each of them >= 0).

%e a(6)=110 since 110=101+9=99+11=88+22=77+33=66+44=55+55 and no

%e number less than 110 has 6 such decompositions.

%t palQ[n_] := n == FromDigits@Reverse@IntegerDigits@n; pt = Select[Range[0, 50005], palQ]; t = Array[0&, 50000]; Do[v = pt[[i]]+pt[[j]]; If[v<50000, t[[v + 1]]++ ], {i, 600}, {j, i}]; Table[Position[t, k][[1, 1]]-1, {k, 55}]

%Y Cf. A035137, A115337.

%K base,nonn

%O 1,2

%A _Giovanni Resta_, Jan 20 2006

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