A379797 - OEIS

A379797

In A377091, each block of consecutive terms of the same sign is followed by a jump of magnitude +-s^2 for some integer s>0 to a term of the opposite sign; sequence lists the successive values of s.

2, 2, 3, 3, 4, 5, 5, 6, 6, 7, 7, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 14, 14, 15, 15, 16, 16, 17, 17, 18, 18, 19, 20, 20, 21, 21, 22, 22, 23, 23, 24, 24, 25, 26, 26, 27, 27, 28, 28, 29, 29, 30, 30, 31, 31, 31, 32, 32, 32, 33, 33, 33, 33, 34, 34, 35, 35, 35, 36, 36, 37, 37, 37, 38, 38, 38, 39, 39, 39, 39, 40, 40, 40, 40, 41, 41

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

OFFSET

1,1

LINKS

N. J. A. Sloane, Table of n, a(n) for n = 1..1024

FORMULA

If n = 2*k-1, k>=1, then a(n) = sqrt{A379791(k)-A379793(k)}; if n = 2k, k>=1, then a(n) = sqrt{A379789(k+1)-A379066(k)}.

EXAMPLE

The initial terms of A377091 are

0, 1, 2, -2, -1, 3, 4, 5, -4, -3, 6, 7, 8, -8, -7, -6, -5, -9, -10, -11, -12, 13, 9, 10, 11, 12, -13, -14

and the jumps we are talking about are

__________4______4_________9______9________16__________________________________25__________________25_____

whose square roots are 2, 2, 3, 3, 4, 5, 5, ... which is the current sequence. - N. J. A. Sloane, Mar 30 2025

CROSSREFS

Cf. A377091, A379066, A379788-A379794, A380837.

See A379798 for first differences.

Sequence in context: A309093 A085268 A214656 * A194979 A366502 A098294

Adjacent sequences: A379794 A379795 A379796 * A379798 A379799 A379800

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Jan 18 2025

STATUS

approved