A376934 Lexicographically earliest sequence of positive integers a(1), a(2), a(3), ... such that for any n > 0, Sum_{k = 1..n} 1/(k*a(k)) < Pi.

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 6, 80, 21896, 604163887, 677040508659246685, 447405708743254015046365510044832005, 309471557529368331206803181535934923519436869019793750609292014082198479

Offset

1,13

Links

Scott R. Shannon, Table of n, a(n) for n = 1..27

Example

a(17) = 604163887 as Sum_{k = 1..17} 1/(k*a(k)) = 1/(1*1) + 1/(2*1) + ... + 1/(16*21896) + 1/(17*604163887) = 3056398076673607759/972881723918332800, which is ~8.2*10^-20 less than Pi.

Crossrefs

Cf. A000796, A270744, A375781, A375529, A074631, A270752.

Sequence in context: A213138 A364798 A349875 * A331403 A357245 A157197

Adjacent sequences: A376931 A376932 A376933 * A376935 A376936 A376937

Keyword

nonn

Author

Scott R. Shannon, Oct 11 2024

Status

approved