A131437 - OEIS

A131437

(A000012 * A131436) + (A131436 * A000012) - A000012.

1, 3, 5, 7, 9, 13, 15, 17, 21, 29, 31, 33, 37, 45, 61, 63, 65, 69, 77, 93, 125, 127, 129, 133, 141, 157, 189, 253, 255, 257, 261, 269, 285, 317, 381, 509, 511, 513, 517, 525, 541, 573, 637, 765, 1021, 1023, 1025, 1029, 1037, 1053, 1085, 1149, 1277, 1533, 2045

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OFFSET

1,2

COMMENTS

Left column = 2^n - 1; right border = A036563, 2^(n+1) - 3: (1, 5, 13, 29, 61, 125, ...). Row sums = A131438: (1, 8, 29, 82, 207, 492, 1129, ...).

LINKS

Table of n, a(n) for n=1..55.

FORMULA

(A000012 * A131436) + (A131436 * A000012) - A000012; as infinite lower triangular matrices.

EXAMPLE

First few rows of the triangle are:

3, 5;

7, 9, 13;

15, 17, 21, 29;

31, 33, 37, 45, 61;

63, 65, 69, 77, 93, 125;

...

MAPLE

A000012 := proc(n, k)

1 ;

end proc:

A131436 := proc(n, k)

if k = n then

2^n-1 ;

else

end if;

end proc:

A131437 := proc(n, k)

add( A000012(n, i)*A131436(i, k) + A131436(n, i)*A000012(i, k), i=k..n) -1 ;

end proc:

seq(seq(A131437(n, k), k=1..n), n=1..15) ; # R. J. Mathar, Sep 24 2011

CROSSREFS

Cf. A036563, A131436, A131438, A131439.

Sequence in context: A307001 A331589 A063951 * A003553 A003532 A156982

Adjacent sequences: A131434 A131435 A131436 * A131438 A131439 A131440

KEYWORD

nonn,easy,tabl

AUTHOR

Gary W. Adamson, Jul 11 2007

EXTENSIONS

Corrected by R. J. Mathar, Sep 24 2011

STATUS

approved