[go: up one dir, main page]

login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A296357
a(n) = ceiling of n/Pi.
1
1, 1, 1, 2, 2, 2, 3, 3, 3, 4, 4, 4, 5, 5, 5, 6, 6, 6, 7, 7, 7, 8, 8, 8, 8, 9, 9, 9, 10, 10, 10, 11, 11, 11, 12, 12, 12, 13, 13, 13, 14, 14, 14, 15, 15, 15, 15, 16, 16, 16, 17, 17, 17, 18, 18, 18, 19, 19, 19, 20, 20, 20, 21, 21, 21, 22, 22, 22, 22, 23, 23, 23, 24, 24, 24, 25, 25, 25, 26, 26, 26, 27, 27
OFFSET
1,4
COMMENTS
The problem asks if a(n) is also equal to ceiling(cosec(Pi/n)) for n>3.
First differs from ceiling(cosec(Pi/n)) for n>3 at n=80143857 (Stadler, 2019; Velleman and Wagon, 2020). - Amiram Eldar, Nov 08 2020
REFERENCES
Daniel J. Velleman and Stan Wagon, Bicycle or Unicycle?, MAA Press, 2020, pp. 32 and 192-194.
LINKS
Jonathan D. Lee and Stan Wagon, Proposers, Problem 12006, The American Mathematical Monthly, Vol. 124, No. 10 (2017), p. 970.
Albert Stadler and others, A Suspicious Formula Involving Pi, solution to Problem 12006, The American Mathematical Monthly, Vol. 126, No. 5 (2019), pp. 475-476.
MATHEMATICA
a[n_] := Ceiling[n/Pi]; Array[a, 100] (* Amiram Eldar, Nov 08 2020 *)
PROG
(PARI) a(n)=n\Pi+1 \\ Charles R Greathouse IV, Mar 04 2018
CROSSREFS
Cf. A032615.
Sequence in context: A079001 A032615 A261231 * A002264 A086161 A008620
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Dec 15 2017
STATUS
approved