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A248873
a(n) = floor(e^(n+1) - e^n).
3
1, 4, 12, 34, 93, 255, 693, 1884, 5122, 13923, 37847, 102880, 279658, 760190, 2066413, 5617093, 15268842, 41505016, 112822331, 306682894, 833650539, 2266097111, 6159890600, 16744318683, 45515777207, 123724710091, 336318631172, 914208823689, 2485077232852, 6755140284380
OFFSET
0,2
COMMENTS
e^(n+1)-e^n-1 < a(n) <= A064780(n) <= a(n)+1 < e^(n+1)-e^n+1.
Lim_{n->infinity} a(n)/e^(n+1) = (e-1)/e. [Corrected by Altug Alkan, Apr 25 2018]
LINKS
Eric Weisstein's World of Mathematics, e
Eric Weisstein's World of Mathematics, Floor Function
FORMULA
a(n) = floor(e^(n+1)-e^n).
MATHEMATICA
Floor[#[[2]]-#[[1]]]&/@Partition[E^Range[0, 30], 2, 1] (* Harvey P. Dale, Jul 24 2018 *)
PROG
(PARI) vector(30, n, n--; floor(exp(n+1)-exp(n))) \\ Michel Marcus, Mar 06 2015
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Danny Rorabaugh, Mar 04 2015
STATUS
approved