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A077552
Consider the following triangle in which the n-th row contains n distinct numbers whose product is the smallest and has the least possible number of divisors. 1 is a member of only the first row. Sequence contains the final term of the rows (the leading diagonal).
6
1, 3, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384, 32768, 65536, 131072, 262144, 524288, 1048576, 2097152, 4194304, 8388608, 16777216, 33554432, 67108864, 134217728, 268435456, 536870912, 1073741824, 2147483648
OFFSET
0,2
COMMENTS
N points are chosen on a circle to get n arcs of different lengths. Then a(n-1) counts - Anton Zakharov, Dec 14 2016
FORMULA
For n>2, a(n)=2^n. - Ray Chandler, Aug 21 2003
Row sums of triangle A132309. - Gary W. Adamson, Aug 18 2007
EXAMPLE
Triangle begins
1
2 3
2 4 8
2 4 8 16
2 4 8 16 32
MATHEMATICA
Table[2^(n + 1) - Boole[n < 2], {n, 0, 30}] (* Michael De Vlieger, Mar 15 2017 *)
CROSSREFS
Cf. A132309.
Sequence in context: A005103 A001978 A173283 * A171497 A024623 A337118
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Nov 10 2002
EXTENSIONS
Corrected and extended by Ray Chandler, Aug 21 2003
STATUS
approved