A257775 Decimal expansion of (e/2)^2.

1, 8, 4, 7, 2, 6, 4, 0, 2, 4, 7, 3, 2, 6, 6, 2, 5, 5, 6, 8, 0, 7, 6, 0, 6, 8, 6, 5, 1, 4, 3, 7, 5, 1, 9, 5, 3, 2, 9, 5, 0, 7, 8, 8, 9, 2, 6, 3, 7, 9, 6, 1, 8, 3, 1, 0, 2, 1, 7, 8, 1, 9, 5, 5, 6, 3, 0, 6, 4, 3, 4, 4, 9, 0, 1, 9, 7, 6, 4, 4, 4, 0, 8, 4, 6, 0, 7, 8, 1, 2, 1, 2, 6, 9, 7, 8, 0, 4, 4, 8, 6, 9, 3, 4, 3

Offset

1,2

Comments

The coefficient a of the unique parabola y = a*x^2 which, at some x > 0, kisses the exponential function y = exp(x). The kissing point coordinates are (2,e^2).

Links

Stanislav Sykora, Table of n, a(n) for n = 1..2000

Example

1.847264024732662556807606865143751953295078892637961831021781955630...

Mathematica

RealDigits[Exp[2]/4, 10, 120][[1]] (* Amiram Eldar, Jun 26 2023 *)

Prog

(PARI) exp(2)/4

Crossrefs

Cf. A001113, A019739, A257776, A257777.

Sequence in context: A096427 A380982 A176453 * A242023 A249415 A021122

Adjacent sequences: A257772 A257773 A257774 * A257776 A257777 A257778

Keyword

nonn,cons,easy

Author

Stanislav Sykora, May 12 2015

Status

approved