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A267747
Numbers k such that k mod 2 = k mod 3 = k mod 5.
1
0, 1, 30, 31, 60, 61, 90, 91, 120, 121, 150, 151, 180, 181, 210, 211, 240, 241, 270, 271, 300, 301, 330, 331, 360, 361, 390, 391, 420, 421, 450, 451, 480, 481, 510, 511, 540, 541, 570, 571, 600, 601, 630, 631, 660, 661, 690, 691, 720, 721, 750, 751, 780, 781, 810, 811, 840
OFFSET
1,3
COMMENTS
Numbers k such that k == 0 or 1 (mod 30). - Robert Israel, Jan 20 2016
FORMULA
a(n) = 15*n - 7*(-1)^n - 22.
G.f.: x^2*(29*x+1)/((x-1)^2*(x+1)).
MATHEMATICA
Table[15*n - 7*(-1)^n - 22, {n, 1000}] (* Or *)
Select[ Range[0, 20000], (Mod[#, 2]==Mod[#, 3]==Mod[#, 5]) &]
LinearRecurrence[{1, 1, -1}, {0, 1, 30}, 60] (* Harvey P. Dale, Nov 15 2021 *)
PROG
(PARI) concat(0, Vec(x^2*(29*x+1)/((x-1)^2*(x+1)) + O(x^60))) \\ Colin Barker, Jan 21 2016
(Magma) [15*n-7*(-1)^n-22: n in [1..60]]; // Vincenzo Librandi, Jan 21 2016
CROSSREFS
Cf. A267711.
Sequence in context: A003896 A114964 A341745 * A022400 A042812 A042814
KEYWORD
nonn,easy
AUTHOR
Mikk Heidemaa, Jan 20 2016
STATUS
approved