A116547 Permutation of natural numbers generated by 5-rowed array shown below.
0, 5, 1, 10, 6, 2, 15, 11, 7, 3, 20, 16, 12, 8, 4, 25, 21, 17, 13, 9, 30, 26, 22, 18, 14, 35, 31, 27, 23, 19, 40, 36, 32, 28, 24, 45, 41, 37, 33, 29, 50, 46, 42, 38, 34, 55, 51, 47, 43, 39, 60, 56, 52, 48, 44, 65, 61, 57, 53, 49, 70, 66, 62, 58, 54, 75, 71, 67, 63, 59, 80, 76, 72
Offset: 1
Keywords
References
- M. Cerasoli, F. Eugeni and M. Protasi, Elementi di Matematica Discreta, Bologna 1988
- Emanuele Munarini and Norma Zagaglia Salvi, Matematica Discreta,UTET, CittaStudiEdizioni, Milano 1997
Links
- Harvey P. Dale, Table of n, a(n) for n = 1..1000
Programs
-
Maple
0, 5, 1, 10, 6, 2, 15, 11, 7, 3, seq(seq(t + 5*k,t=[15,11,7,3,-1]),k=1..20); # Robert Israel, Mar 23 2017
-
Mathematica
Select[Join[{0},Table[Most[NestList[#-4&,5n,5]],{n,20}]]//Flatten,#>=0&] (* Harvey P. Dale, Nov 26 2016 *)
Formula
Starting with term a(10): a(n+5k) = a(n) + 5k, with k>=1.
G.f.: x*(5-4*x+9*x^2-4*x^3-4*x^4+8*x^5-13*x^7+21*x^9-17*x^10+4*x^14)/(1-x-x^5+x^6). - Robert Israel, Mar 23 2017
Comments