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A047547
Numbers that are congruent to {0, 2, 3, 4, 7} mod 8.
1
0, 2, 3, 4, 7, 8, 10, 11, 12, 15, 16, 18, 19, 20, 23, 24, 26, 27, 28, 31, 32, 34, 35, 36, 39, 40, 42, 43, 44, 47, 48, 50, 51, 52, 55, 56, 58, 59, 60, 63, 64, 66, 67, 68, 71, 72, 74, 75, 76, 79, 80, 82, 83, 84, 87, 88, 90, 91, 92, 95, 96, 98, 99, 100, 103
OFFSET
1,2
FORMULA
From Chai Wah Wu, Jun 10 2016: (Start)
a(n) = a(n-1) + a(n-5) - a(n-6) for n > 6.
G.f.: x^2*(x^4 + 3*x^3 + x^2 + x + 2)/(x^6 - x^5 - x + 1). (End)
From Wesley Ivan Hurt, Jul 28 2016: (Start)
a(n) = a(n-5) + 8 for n>5.
a(n) = (40*n - 40 - 7*(n mod 5) + 3*((n+1) mod 5) + 3*((n+2) mod 5) - 2*((n+3) mod 5) + 3*((n+4) mod 5))/25.
a(5k) = 8k-1, a(5k-1) = 8k-4, a(5k-2) = 8k-5, a(5k-3) = 8k-6, a(5k-4) = 8k-8. (End)
MAPLE
A047547:=n->8*floor(n/5)+[(0, 2, 3, 4, 7)][(n mod 5)+1]: seq(A047547(n), n=0..100); # Wesley Ivan Hurt, Jul 28 2016
MATHEMATICA
Select[Range[0, 100], MemberQ[{0, 2, 3, 4, 7}, Mod[#, 8]]&] (* Harvey P. Dale, Jun 14 2011 *)
PROG
(Magma) [n : n in [0..150] | n mod 8 in [0, 2, 3, 4, 7]]; // Wesley Ivan Hurt, Jul 28 2016
CROSSREFS
Sequence in context: A378269 A302123 A286337 * A014456 A349152 A089190
KEYWORD
nonn,easy
STATUS
approved