A138336 First occurrence of exactly n consecutive numbers after A138335(n) (A138335(n) excluded).

18, 27, 127, 1111

Offset: 1

Author

Artur Jasinski, Mar 15 2008

Keywords

• nonn
• dead

Comments

Such number digits after decimal point of number Pi where the approximation to the number Pi by a root of a polynomial of 2 degree does not improve the accuracy exactly n next digits.

It seems that sequence A138335, and therefore also this sequence, are ill defined. - M. F. Hasler, May 21 2025

Examples

			a(1)=18 because 3.141592653589793238 (18 digits) is root of -3061495 + 674903*x + 95366*x^2 and 3.1415926535897932385 (19 digits) also is root of that same polynomial -3061495 + 674903*x + 95366*x^2.
		

Crossrefs

Cf. A138335, A138337.

Extensions

There are comments in the entry for A138335 which may cast doubt on the validity of this and related sequences. - N. J. A. Sloane, Mar 19 2008