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A007232 Number of free subsets of multiplicative group of GF(5^n).
(Formerly M2077)
1
2, 15, 74, 409, 1951, 9765, 48827, 256347, 1220699, 6103515, 30517572, 160216158, 762939452, 3814697265, 19073486293, 101327896117, 476837158134 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

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

REFERENCES

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.

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

LINKS

Table of n, a(n) for n=1..17.

CROSSREFS

Cf. A007233.

Sequence in context: A125903 A268644 A178321 * A099743 A283842 A102289

Adjacent sequences:  A007229 A007230 A007231 * A007233 A007234 A007235

KEYWORD

nonn

AUTHOR

Simon Plouffe

STATUS

approved

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Last modified December 6 07:00 EST 2019. Contains 329784 sequences. (Running on oeis4.)