login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A119037 Triangular numbers composed of digits {0,1,4}. 2
1, 10, 10011, 10440, 41041, 41001040, 141044410, 1010004040, 4104044101, 14041444410, 114011410040100, 440404440401100, 1041401040044401, 40114114410110140, 14001400401400441011, 1040410404040110411004140 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..16.

G. Resta, Tridigital Triangular Numbers

MATHEMATICA

Rest[Select[FromDigits/@Tuples[{0, 1, 4}, 12], IntegerQ[(Sqrt[8 # + 1] - 1)/2] &]] (* Vincenzo Librandi, Dec 18 2015 *)

PROG

(MAGMA) [t: n in [1..2*10^7] | Set(Intseq(t)) subset {0, 1, 4} where t is n*(n+1) div 2]; // Vincenzo Librandi, Dec 18 2015

CROSSREFS

Cf. A000217, A058414, A119038. See A119033 for a table of cross-references.

Sequence in context: A283890 A139109 A317959 * A327232 A266841 A267677

Adjacent sequences:  A119034 A119035 A119036 * A119038 A119039 A119040

KEYWORD

nonn,base

AUTHOR

Giovanni Resta, May 10 2006

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified November 17 16:07 EST 2019. Contains 329240 sequences. (Running on oeis4.)