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A178348
a(n) = Sum_{k=0..n} 1100^k.
1
1, 1101, 1211101, 1332211101, 1465432211101, 1611975432211101, 1773172975432211101, 1950490272975432211101, 2145539300272975432211101, 2360093230300272975432211101, 2596102553330300272975432211101, 2855712808663330300272975432211101
OFFSET
0,2
FORMULA
a(n) = 1100*a(n-1) + 1.
Lim_{n -> infinity} a(n)/1100^n = 1100/1099.
From Colin Barker, Oct 02 2015: (Start)
a(n) = 1101*a(n-1) - 1100*a(n-2) for n>=2.
G.f.: 1 / ((x-1)*(1100*x-1)). (End)
EXAMPLE
As overlapping Pascal triangles:
.....1
....1.1.0.1
...1.2.1.1.1.0.1
..1.3.3.2.2.1.1.1.0.1
.1.4.6.5.4.3.2.2.1.1.1.0.1
MATHEMATICA
Table[Sum[1100^k, {k, 0, n}], {n, 0, 11}] (* Michael De Vlieger, Oct 02 2015 *)
PROG
(PARI) Vec(1/((x-1)*(1100*x-1)) + O(x^25)) \\ Colin Barker, Oct 02 2015
(PARI) vector(100, n, n--; sum(k=0, n, 1100^k)) \\ Altug Alkan, Oct 06 2015
(Magma) [(1/1099)*(1100^n-1): n in [0..20]]; // Vincenzo Librandi, Oct 07 2015
CROSSREFS
Sequence in context: A283172 A283253 A178407 * A359149 A250796 A271431
KEYWORD
nonn,easy
AUTHOR
Mark Dols, May 25 2010
EXTENSIONS
Offset corrected by Joerg Arndt, Oct 03 2015
STATUS
approved