A073829 a(n) = 4*((n-1)! + 1) + n.

9, 10, 15, 32, 105, 490, 2891, 20172, 161293, 1451534, 14515215, 159667216, 1916006417, 24908083218, 348713164819, 5230697472020, 83691159552021, 1422749712384022, 25609494822912023, 486580401635328024, 9731608032706560025, 204363768686837760026

Offset: 1

Author

Reinhard Zumkeller, Aug 12 2002

Keywords

• nonn
• easy

References

• Paulo Ribenboim, The Little Book of Bigger Primes, Springer-Verlag NY 2004. See p. 192.
• James J. Tattersall, Elementary Number Theory in Nine Chapters, Cambridge University Press, 1999, page 112.

Links

• Winston de Greef, Table of n, a(n) for n = 1..449 (first 200 terms from Vincenzo Librandi)
• P. A. Clement, Congruences for sets of primes, Am. Math. Monthly 56 (1) (1949) 23-25.

Crossrefs

See A073830 for motivation.

Cf. A038507.

Programs

Magma

[4*(Factorial(n-1)+1)+n: n in [1..20]]; // Vincenzo Librandi, May 04 2014

Mathematica

Table[(4 ((n - 1)! + 1) + n), {n, 1, 20}] (* Vincenzo Librandi, May 04 2014 *)

Sage

[4*(factorial(n-1) + 1) + n for n in range(1,22)] # Stefano Spezia, Apr 21 2025