A080483 Reverse concatenation of next n numbers with a(1) = 0.

0, 21, 543, 9876, 1413121110, 201918171615, 27262524232221, 3534333231302928, 444342414039383736, 54535251504948474645, 6564636261605958575655, 777675747372717069686766, 90898887868584838281807978

Offset: 1

Author

Amarnath Murthy, Mar 11 2003

Keywords

• base
• easy
• nonn

Comments

a(n) is a multiple of 3.

Links

• Harvey P. Dale, Table of n, a(n) for n = 1..200

Crossrefs

Cf. A080481, A080482, A080484.

Programs

Mathematica

With[{nn=20},FromDigits[Flatten[IntegerDigits[#]]]&/@(Reverse/@ TakeList[ Range[0,(nn(nn+1))/2],Range[nn]])] (* Requires Mathematica version 11 or later *) (* Harvey P. Dale, Jun 10 2019 *)

Extensions

More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 06 2003