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%I #7 Nov 16 2013 10:12:36
%S 1,2,3,4,5,6,7,8,9,54,271,7846,937767,605772815,87246282837,
%T 547880799393,2399113322502,4137547470482,45252394397843,
%U 1531558595686560,1281758695960501,2008670909471090,3385200300351842,6108670309471325,7985400400619556,8253670509407076
%N Numbers that are sums of substrings of their reversals.
%C a(16) <= 547880799393. [From _Donovan Johnson_, May 25 2009]
%e For example: 54 = 45 + 4 + 5; 271 = 172 + 17 + 72 + 1 + 7 + 2.
%t Select[Table[n, {n, 10000000 }], # == Plus @@ ToExpression[ Flatten[Table[ StringTake[StringReverse[ToString[ # ]], {i, j}], {i, StringLength[ToString[ # ]]}, {j, i, StringLength[ToString[ # ]]}]]] &]
%Y Cf. A121947 - Numbers that are sums of proper substrings of their reversals.
%K base,nonn
%O 1,2
%A _Tanya Khovanova_, Sep 08 2006
%E a(14)-a(15) from _Donovan Johnson_, May 25 2009
%E More terms from _Jon E. Schoenfield_, Nov 15 2013
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