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A116468
Permutation of natural numbers generated by 2-rowed array shown below.
1
2, 3, 1, 6, 4, 7, 5, 10, 8, 11, 9, 14, 12, 15, 13, 18, 16, 19, 17, 22, 20, 23, 21, 26, 24, 27, 25, 30, 28, 31, 29, 34, 32, 35, 33, 38, 36, 39, 37, 42, 40, 43, 41, 46, 44, 47, 45, 50, 48, 51, 49, 54, 52, 55, 53, 58, 56, 59, 57, 62, 60, 63, 61, 66, 64, 67
OFFSET
1,1
COMMENTS
2 3 6 7 10 11 14 15 ... integers congruent to 2 or 3 mod 4
1 4 5 8 9 12 13 16 ... integers congruent to 0 or 1 mod 4
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
FORMULA
For n>2, a(n+4k) = a(n) + 4k, with k>=1.
G.f.: x*(2+x-2*x^2+5*x^3-4*x^4+2*x^5)/(1-x-x^4+x^5). - Philippe Deléham, Dec 02 2016
CROSSREFS
Cf. A090964.
Sequence in context: A223486 A205112 A173161 * A110237 A189970 A076631
KEYWORD
easy,nonn
AUTHOR
Giovanni Teofilatto, Mar 17 2006
EXTENSIONS
Terms corrected by R. J. Mathar, Oct 25 2011
STATUS
approved