A007232 - OEIS

%I M2077 #15 Mar 22 2018 09:48:00

%S 2,15,74,409,1951,9765,48827,256347,1220699,6103515,30517572,

%T 160216158,762939452,3814697265,19073486293,101327896117,476837158134

%N Number of free subsets of multiplicative group of GF(5^n).

%C Observe that a(4*n+2) = (5^(4*n+3) - 5)/8 for n = 0,1,2,3. Does this result hold for general n? - _Peter Bala_, Mar 22 2018

%D P. Bouchard and Y.-N. Yeh, Finding f-free subsets of maximal cardinality, Séries Formelles et Combinatoire Algébrique, 4th colloquium, 15-19 Juin 1992, Montréal, Université du Québec à Montréal, pp. 11-17.

%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

%Y Cf. A007233.

%K nonn

%O 1,1

%A _Simon Plouffe_