A157425 Numbers which can be represented using fewer symbols than the number of decimal digits in the number.

120, 125, 128, 216, 243, 256, 343, 512, 625, 720, 729, 1000, 1024, 1089, 1156, 1225, 1296, 1331, 1369, 1444, 1521, 1600, 1681, 1728, 1764, 1849, 1936, 2025, 2048, 2116, 2187, 2197, 2209, 2304, 2401, 2500, 2601, 2704, 2744, 2809, 2916, 3025, 3125, 3136

Offset

1,1

Comments

The "up-arrow" symbol is free, since that is indicated by a superscript.

Additional terms are possible if the double factorial (!!) operator is permitted. [From Sean A. Irvine, Mar 14 2010]

Links

Table of n, a(n) for n=1..44.

Example

120=5!, 125=5^3, ..., 59050 = 9^5 + 1, ..., 1354984 = 9^6 + 7^7, ...

Crossrefs

Sequence in context: A085218 A296884 A117645 * A030501 A271578 A297152

Adjacent sequences: A157422 A157423 A157424 * A157426 A157427 A157428

Keyword

base,nonn

Author

Alan Frank, Feb 28 2009

Extensions

Edited by N. J. A. Sloane, Mar 27 2009

Corrected and extended by Sean A. Irvine, Mar 14 2010

Status

approved