A121535 Numbers that are sums of substrings of their reversals.

1, 2, 3, 4, 5, 6, 7, 8, 9, 54, 271, 7846, 937767, 605772815, 87246282837, 547880799393, 2399113322502, 4137547470482, 45252394397843, 1531558595686560, 1281758695960501, 2008670909471090, 3385200300351842, 6108670309471325, 7985400400619556, 8253670509407076

Offset

1,2

Comments

a(16) <= 547880799393. [From Donovan Johnson, May 25 2009]

Links

Table of n, a(n) for n=1..26.

Example

For example: 54 = 45 + 4 + 5; 271 = 172 + 17 + 72 + 1 + 7 + 2.

Mathematica

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

Crossrefs

Cf. A121947 - Numbers that are sums of proper substrings of their reversals.

Sequence in context: A327735 A133287 A133377 * A082743 A083838 A087082

Adjacent sequences: A121532 A121533 A121534 * A121536 A121537 A121538

Keyword

base,nonn

Author

Tanya Khovanova, Sep 08 2006

Extensions

a(14)-a(15) from Donovan Johnson, May 25 2009

More terms from Jon E. Schoenfield, Nov 15 2013

Status

approved