

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
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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 crossreferences.
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



