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Positive numbers that are sums of proper substrings of their reversals.
1

%I #27 Nov 19 2013 12:46:22

%S 149,198,1392,16041957,10000000009,132324898229,154879506575,

%T 14501949763339,15509886785307493,16314428059046884,

%U 1589868655913263939

%N Positive numbers that are sums of proper substrings of their reversals.

%C a(12) > 10^20. - _Jon E. Schoenfield_, Nov 15 2013

%e 149 is in the sequence because 149 = 1 + 4 + 9 + 41 + 94.

%t Select[Table[ n, {n, 10000000}], # == Plus @@ ToExpression[ Flatten[Table[ StringTake[StringReverse[ToString[ # ]], {i, j}], {i, StringLength[ToString[ # ]]}, {j, i, StringLength[ToString[ # ]]}]]] - ToExpression[StringReverse[ToString[ # ]]] &]

%Y Cf. A121535.

%K base,more,nonn

%O 1,1

%A _Tanya Khovanova_, Sep 04 2006

%E a(4) from _Donovan Johnson_, Mar 30 2010

%E a(5) from _Jon E. Schoenfield_, Nov 12 2013

%E a(6) - a(11) from _Jon E. Schoenfield_, Nov 13 2013