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A007652
Final digit of prime(n).
(Formerly M0632)
57
2, 3, 5, 7, 1, 3, 7, 9, 3, 9, 1, 7, 1, 3, 7, 3, 9, 1, 7, 1, 3, 9, 3, 9, 7, 1, 3, 7, 9, 3, 7, 1, 7, 9, 9, 1, 7, 3, 7, 3, 9, 1, 1, 3, 7, 9, 1, 3, 7, 9, 3, 9, 1, 1, 7, 3, 9, 1, 7, 1, 3, 3, 7, 1, 3, 7, 1, 7, 7, 9, 3, 9, 7, 3, 9, 3, 9, 7, 1, 9, 9, 1, 1, 3, 9, 3, 9, 7, 1, 3, 7, 9, 7, 1, 9, 3, 9, 1, 3, 1, 7, 7, 3, 9, 1
OFFSET
1,1
COMMENTS
Primes modulo 10.
REFERENCES
Milton Abramowitz and Irene A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, 1964 (and various reprintings), p. 870.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
Milton Abramowitz and Irene A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards, Applied Math. Series 55, Tenth Printing, 1972 [alternative scanned copy].
Alberto Fraile et al., Prime numbers and random walks in a square grid, Phys. Rev. E, 104(5) (2021), 054114.
Evelyn Lamb, "Peculiar Pattern Found in 'Random' Prime Numbers", Nature, March 14, 2016, republished by Scientific American.
Robert J. Lemke Oliver and Kannan Soundararajan, Unexpected biases in the distribution of consecutive primes, arXiv preprint arXiv:1603.03720 [math.NT], 2016.
FORMULA
a(n) = A010879(A000040(n)). - Michel Marcus, May 06 2014
Sum_k={1..n} a(k) ~ 5*n. - Amiram Eldar, Dec 11 2024
MAPLE
seq(ithprime(n) mod 10, n=1..105); # Nathaniel Johnston, Jun 29 2011
MATHEMATICA
Table[Mod[Prime[n], 10], {n, 120}] (* Ray Chandler, Oct 01 2005 *)
Mod[Prime[Range[100]], 10] (* Vincenzo Librandi, May 06 2014 *)
PROG
(Magma) [Intseq(p)[1]: p in PrimesUpTo(600)]; // Bruno Berselli, Feb 14 2013
(Magma) [p mod 10: p in PrimesUpTo(500)]; // Vincenzo Librandi, May 06 2014
(PARI) a(n)=prime(n)%10 \\ Charles R Greathouse IV, Oct 13 2016
(PARI) primes(100)%10 \\ Charles R Greathouse IV, Oct 13 2016
KEYWORD
nonn,base,easy
EXTENSIONS
Extended by Ray Chandler, Oct 01 2005
STATUS
approved