login
The OEIS is supported by
the many generous donors to the OEIS Foundation
.
Hints
(Greetings from
The On-Line Encyclopedia of Integer Sequences
!)
A119204
Triangular numbers composed of digits {4,5,7}.
2
45, 55, 5747745, 744574755, 77545447574475, 4745745457757444544544575, 44477447457545755547775754555, 547457575775574544754447747777455
(
list
;
graph
;
refs
;
listen
;
history
;
text
;
internal format
)
OFFSET
1,1
COMMENTS
a(8) > 10^40. -
Tyler Busby
, Mar 28 2023
LINKS
Table of n, a(n) for n=1..8.
Giovanni Resta,
Tridigital Triangular Numbers
.
FORMULA
a(n) =
A000217
(
A119205
(n)). -
Jon E. Schoenfield
, Mar 27 2023
CROSSREFS
Cf.
A000217
,
A053951
,
A119205
. See
A119033
for a table of cross-references.
Sequence in context:
A068812
A119071
A119158
*
A119206
A060463
A206024
Adjacent sequences:
A119201
A119202
A119203
*
A119205
A119206
A119207
KEYWORD
nonn
,
base
,
more
AUTHOR
Giovanni Resta
, May 10 2006
EXTENSIONS
a(8) from
Tyler Busby
, Mar 28 2023
STATUS
approved
Lookup
|
Welcome
|
Wiki
|
Register
|
Music
|
Plot 2
|
Demos
|
Index
|
Browse
|
More
|
WebCam
Contribute new seq. or comment
|
Format
|
Style Sheet
|
Transforms
|
Superseeker
|
Recents
The OEIS Community
| Maintained by
The OEIS Foundation Inc.
License Agreements, Terms of Use, Privacy Policy.
.
Last modified April 24 20:08 EDT 2024. Contains 371963 sequences. (Running on oeis4.)