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A143088 Triangle T(n,m)=( 2^(m+1)-1 ) * ( 2^(n-m+1)-1 ), read by rows, 0<=m<=n. 1
1, 3, 3, 7, 9, 7, 15, 21, 21, 15, 31, 45, 49, 45, 31, 63, 93, 105, 105, 93, 63, 127, 189, 217, 225, 217, 189, 127, 255, 381, 441, 465, 465, 441, 381, 255, 511, 765, 889, 945, 961, 945, 889, 765, 511, 1023, 1533, 1785, 1905, 1953, 1953, 1905, 1785, 1533, 1023, 2047 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Row sums are A045618.

LINKS

Table of n, a(n) for n=0..55.

FORMULA

T(n,m) = T(n,n-m).

EXAMPLE

1;

3, 3;

7, 9, 7;

15, 21, 21, 15;

31, 45, 49, 45, 31;

63, 93, 105, 105, 93, 63;

127, 189, 217, 225, 217, 189, 127;

255, 381, 441, 465, 465, 441, 381, 255;

511, 765, 889, 945, 961, 945, 889, 765, 511;

1023, 1533, 1785, 1905, 1953, 1953, 1905, 1785, 1533, 1023;

2047, 3069, 3577, 3825, 3937, 3969, 3937, 3825, 3577, 3069, 2047;

MATHEMATICA

Table[Table[(2^(m + 1) - 1)*(2^(n - m + 1) - 1), {m, 0, n}], {n, 0, 10}]; Flatten[%]

CROSSREFS

Cf. A000225 (first column), A068156 (second column).

Sequence in context: A213942 A144554 A177936 * A131036 A206433 A301589

Adjacent sequences:  A143085 A143086 A143087 * A143089 A143090 A143091

KEYWORD

nonn,tabl

AUTHOR

Roger L. Bagula and Gary W. Adamson, Oct 16 2008

STATUS

approved

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Last modified November 13 12:45 EST 2019. Contains 329094 sequences. (Running on oeis4.)