OFFSET
1,1
COMMENTS
Subsequence of A034049.
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
S. Giraudo, Combinatorial operads from monoids, arXiv preprint arXiv:1306.6938 [math.CO], 2013-2015. See Sect. 3.2.1.
MAPLE
f:= proc(d) local b, i;
b:= (10^d-1)/9;
seq(b+10^i, i=0..d-1);
end proc:
seq(f(d), d=1..9); # Robert Israel, Jan 13 2021
PROG
(PARI) one(n)=if(n, 10^n\9, "")
for(n=0, 9, for(m=0, n, print1(one(n-m)2one(m)", "))) \\ Charles R Greathouse IV, Nov 13 2011
(Python)
def athrough(k1s):
return [int("1"*(i-j)+"2"+"1"*j) for i in range(k1s+1) for j in range(i+1)]
print(athrough(8)) # Michael S. Branicky, Feb 12 2021
CROSSREFS
KEYWORD
nonn,easy,base
AUTHOR
Jaroslav Krizek, Nov 13 2011
STATUS
approved