A080172 Final digit of n-th Mersenne prime A000668(n).
3, 7, 1, 7, 1, 1, 7, 7, 1, 1, 7, 7, 1, 7, 7, 7, 1, 1, 1, 7, 1, 1, 1, 1, 1, 1, 1, 7, 7, 1, 7, 7, 1, 7, 1, 1, 1, 1, 1, 7, 7, 7, 1, 1, 7, 1, 1, 1
Offset: 1
References
- G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers. 3rd ed., Oxford Univ. Press, 1954, p. 16.
Links
- Great Internet Mersenne Prime Search (GIMPS), Distributed Computing Projects
- Mersenne Primes, History, Theorems and Lists
Programs
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Maple
(Maple code from N. J. A. Sloane) # let s1 := list of terms in A000043 f:=n->if n mod 4 = 0 then 4 else n mod 4; fi; map(x->2^f(x)-1,s1);
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Mathematica
Mod[2^MersennePrimeExponent[Range[48]]-1,10] (* Harvey P. Dale, Aug 09 2023; updated by Mark Dowdeswell, Sep 16 2024 *)
Extensions
Updated by N. J. A. Sloane, Apr 01 2008
a(40)-a(47) from Ivan Panchenko, Apr 11 2018
a(48) from Mark Dowdeswell, Sep 16 2024
Comments