OFFSET
1,2
EXAMPLE
Triangle begins:
1
2 1 2
4 2 1 2 4
8 4 2 1 2 4 8
16 8 4 2 1 2 4 8 16
32 16 8 4 2 1 2 4 8 16 32
64 32 16 8 4 2 1 2 4 8 16 32 64
128 64 32 16 8 4 2 1 2 4 8 16 32 64 128
256 128 64 32 16 8 4 2 1 2 4 8 16 32 64 128 256
512 256 128 64 32 16 8 4 2 1 2 4 8 16 32 64 128 256 512
1024 512 256 128 64 32 16 8 4 2 1 2 4 8 16 32 64 128 256 512 1024
... - Philippe Deléham, Mar 20 2013
MATHEMATICA
pow2Pyram[row_] := Module[{st = 2^Range[0, row]}, Join[st, Reverse[Most[Rest[st]]]]]; Flatten[Array[pow2Pyram, 10]] (* Harvey P. Dale, May 09 2012 *)
Flatten[Table[Table[2^Abs[col], {col, -row, row}], {row, 0, 7}]] (* Alonso del Arte, Apr 15 2017 *)
PROG
(PARI) for(i=0, 9, forstep(j=i, 0, -1, print1(1<<j", ")); for(j=1, i, print1(1<<j", "))) \\ Charles R Greathouse IV, Mar 20 2013
CROSSREFS
KEYWORD
nonn,tabf,easy
AUTHOR
Benoit Cloitre, Apr 12 2003
STATUS
approved