

A137840


Number of distinct nary operators in a quaternary logic.


3



4, 256, 4294967296, 340282366920938463463374607431768211456, 13407807929942597099574024998205846127479365820592393377723561443721764030073546976801874298166903427690031858186486050853753882811946569946433649006084096
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OFFSET

0,1


COMMENTS

The total number of nary operators in a kvalued logic is T = k^(k^n), i.e. if S is a set of k elements, there are T ways of mapping an ordered subset of n elements taken from S to an element of S. Some operators are "degenerate": the operator has arity p, if only p of the n input values influence the output. Therefore the set of operators can be partitioned into n+1 disjoint subsets representing arities from 0 to n.


LINKS

Table of n, a(n) for n=0..4.


FORMULA

a(n) = 4^(4^n)


CROSSREFS

Cf. A001146 = the number of distinct nary operators in a binary logic. A055777 = the number of distinct nary operators in a ternary logic. A137841 = the number of distinct nary operators in a quinternary logic.
Sequence in context: A136807 A057156 A132656 * A114561 A252586 A214136
Adjacent sequences: A137837 A137838 A137839 * A137841 A137842 A137843


KEYWORD

easy,nonn


AUTHOR

Ross Drewe, Feb 13 2008


STATUS

approved



