A011778 Numbers k where A011776(k) grows.

2, 6, 12, 24, 36, 40, 45, 48, 60, 72, 80, 90, 120, 144, 180, 240, 360, 480, 630, 672, 720, 1080, 1120, 1260, 1344, 1440, 1890, 2016, 2160, 2240, 2520, 2880, 3024, 3360, 3780, 4032, 4320, 5040, 6048

Offset

1,1

Comments

Equivalently, 2 along with numbers A092427(j) where A092427(j) > A092427(j-1), for j > 0. - Derek Orr, Apr 16 2015

Is 45 the only odd number in this sequence? - Derek Orr, Apr 16 2015

a(184) = 212837625 and a(311) = 638512875 are the only other odd terms < 10^11. - Charlie Neder, Jan 27 2019

References

Ivan Niven, Herbert S. Zuckerman and Hugh L. Montgomery, An Introduction to the Theory Of Numbers, Fifth Edition, Wiley NY 1991.

J. Roberts, Lure of the Integers, Math. Assoc. America, 1992, p. 251.

Links

Charlie Neder, Table of n, a(n) for n = 1..697 (terms < 10^11; first 100 terms from T. D. Noe)

Index entries for sequences related to factorial numbers

Formula

a(n) = A061769(n) + 1.

a(n) = A092427(A061770(n)). - Derek Orr, Apr 16 2015

Crossrefs

Cf. A011776, A011777, A133481, A092427.

Sequence in context: A137895 A194096 A099993 * A067718 A210594 A307252

Adjacent sequences: A011775 A011776 A011777 * A011779 A011780 A011781

Keyword

nonn,nice,easy

Author

Robert G. Wilson v

Extensions

Corrected by Vladeta Jovovic, Dec 01 2002

Status

approved