The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A291719 Numbers occurring in Ezra Ehrenkrantz's "Modular Coordination System". 4
 1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, 16, 18, 20, 24, 27, 30, 32, 36, 40, 45, 48, 54, 60, 64, 72, 80, 90, 96, 108, 120, 128, 144, 180, 192, 216, 240, 288, 360, 384, 432, 576, 720, 1152 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Cited from Jay Kapraff’s article: "... architect Ezra Ehrenkrantz created a system of architectural proportion that incorporates aspects of Alberti’s and Palladio’s systems made up of lengths factorable by the primes 2, 3, and 5, along with the additive properties of Fibonacci series." REFERENCES Ezra Ehrenkrantz, Modular Number Pattern, Tiranti, London 1956. LINKS Jay Kappraff, Musical Proportions at the Basis of Systems of Architectural Proportion both Ancient and Modern, Chapter 37 in Volume I of K. Williams and M.J. Ostwald (eds.), Architecture and Mathematics from Antiquity to the Future, DOI 10.1007/978-3-319-00137-1_37, Springer International Publishing Switzerland 2015 FORMULA Numbers of the form Fibonacci(i+2)*2^j*3^k; i, j=0..4, k=0..2. EXAMPLE The number pattern in three dimensions:                      A    B     C     D     E           Plate 3 +---+-----+-----+-----+-----+                  /|  9   18    36    72   144 |                 / | 18   36    72   144   288 |                /  | 27   54   108   216   432 |               /   | 45   90   180   360   720 |              /    | 72  144   288   576  1152 |             /     +---+-----+-----+-----+-----+            / A    B     C     D     E        /   Plate 2 /---+-----+-----+-----+-----+     /          /|  3    6    12    24    48 |    /         / |  6   12    24    48    96 |   /        /  |  9   18    36    72   144 |  /       /   | 15   30    60   120   240 | /      /    | 24   48    96   192   384 |/     /     +---+-----+-----+-----+-----/    /  A    B     C     D     E       /   +---+-----+-----+-----+-----+ Plate 1   |  1    2     4     8    16 |    /   |  2    4     8    16    32 |   /   |  3    6    12    24    48 |  /   |  5   10    20    40    80 | /   |  8   16    32    64   128 |/   +---+-----+-----+-----+-----+ MAPLE with(combinat): {seq(seq(seq(fibonacci(i+2)*2^j*3^k, k=0..2), j=0..4), i=0..4)}[]; # Alois P. Heinz, Aug 30 2017 CROSSREFS Cf. A000045, A051037. Sequence in context: A257997 A070023 A035303 * A018609 A243390 A029461 Adjacent sequences:  A291716 A291717 A291718 * A291720 A291721 A291722 KEYWORD nonn,fini,full AUTHOR Hugo Pfoertner, Aug 30 2017 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified June 24 16:44 EDT 2021. Contains 345417 sequences. (Running on oeis4.)