OFFSET
1,2
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..200
EXAMPLE
a(4) = 98710 formed by using digits of 7,8,9 and 10.
MATHEMATICA
FromDigits[Sort[Flatten[IntegerDigits/@#], Greater]]&/@Table[ Reverse[ Range[ (n(n+1))/2+1, ((n+1)(n+2))/2]], {n, 0, 15}] (* Harvey P. Dale, May 13 2017 *)
PROG
(Python)
def a(n):
s = "".join(sorted("".join(map(str, range((n-1)*n//2+1, n*(n+1)//2+1)))))
return int("".join(sorted(s, reverse=True)))
print([a(n) for n in range(1, 15)]) # Michael S. Branicky, Jan 23 2021
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
Amarnath Murthy, Mar 11 2003
EXTENSIONS
More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 19 2003
More terms from Harvey P. Dale, May 13 2017
STATUS
approved