A025486 - OEIS

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A025486

Least k with A025485(k) = n.

0

0, 3, 5, 10, 26, 170, 7226, 13053770, 42600227803226, 453694852221687377444001770, 51459754733114686962148583993443846186613037940783226

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,2

LINKS

Table of n, a(n) for n=0..10.

FORMULA

For n >= 4, a(n) = a(n-1)^2/4+1.

Conjecture: a(n) = A006892(n+1)+3 for n >= 3. - R. J. Mathar, Apr 23 2007

CROSSREFS

Sequence in context: A243516 A243517 A243518 * A011969 A003187 A262306

Adjacent sequences: A025483 A025484 A025485 * A025487 A025488 A025489

KEYWORD

nonn

AUTHOR

David W. Wilson

EXTENSIONS

Title corrected and missing a(1)=3 inserted by Sean A. Irvine, Aug 31 2019

STATUS

approved