A119182 - OEIS

A119182

Triangular numbers composed of digits {3,4,5}.

3, 45, 55, 435, 34453, 455535, 3355345, 3544453, 45453345, 334434453, 355444453, 3433345545, 4544333445, 5435334453, 35554444453, 44555453355, 3555544444453, 53443433535355, 355555444444453, 454555345444453, 5355435453444453, 35455445544444555

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Table of n, a(n) for n=1..22.

Giovanni Resta, Tridigital Triangular Numbers

FORMULA

a(n) = A000217(A119183(n)).

MATHEMATICA

Select[Flatten[Table[FromDigits/@Tuples[{3, 4, 5}, n], {n, 17}]], OddQ[Sqrt[8#+1]]&] (* Harvey P. Dale, Nov 15 2025 *)

CROSSREFS

Cf. A000217, A053937, A119183. See A119033 for a table of cross-references.

Sequence in context: A212999 A103980 A101236 * A178337 A161589 A360966

Adjacent sequences: A119179 A119180 A119181 * A119183 A119184 A119185

KEYWORD

nonn,base

AUTHOR

Giovanni Resta, May 10 2006

EXTENSIONS

a(21)-a(22) from Tyler Busby, Mar 24 2023

STATUS

approved