A169627 A conjectured sequence of bud numbers for eucalyptus flowers.

1, 3, 7, 13, 21, 31

Offset: 0

Author

N. J. A. Sloane, based on email from Omar E. Pol, Mar 07 2010

Keywords

• nonn
• more

Comments

The Carr and Carr article says: "Pryor (1954) has postulated three developmental series of bud numbers, as follows : (a) 1, 3, 7, 11, 15, 23, 35 ... (b) 1, 3, 7, 13, 21, 31 ...; (c) 1, 3, 15, 31, 63, 127 ..."

It would be nice to have more information.

The given terms (corresponding to (b) above) would match the formula a(n)=n^2+n+1, as suggested (with offset corrected) on the Weidmann's web page, cf. LINKS. This would mean that a(n) = A002061(n+1). But based on the construction and illustration in the Pryor paper, it could as well be a duplicate of A161206. The first terms also coincide with the Treillis sequence A115298. - M. F. Hasler, Apr 14 2015

Links

• D. J. Carr and S. G. M. Carr, Developmental morphology of the floral organs of Eucalyptus. I. The inflorescence, Austr. J. Botany 7(2) (1959), 109-141. [2.6 MB, may need longer to load], (a link with less information. The main links are below).
• L. D. Pryor, Illustration of initial terms (Fig. 2b)
• L. D. Pryor, The inheritance of inflorescence characters in Eucalyptus, Proceedings of the Linnean Society of New South Wales, V. 79, (1954), p. 79-89. [From _Omar E. Pol_, Mar 07 2010]
• P. E. Weidmann, The OEIS Sequencer survey, Apr 11 2015

Crossrefs

Cf. A169626.

Extensions

Added information to the Carr & Carr link. - R. J. Mathar, Mar 08 2010