A081542 - OEIS

A081542

Row sums of A081541.

0, 3, 84, 1605, 25926, 380247, 5234568, 68888889, 876543210, 10864197531, 1022851851852, 112533839506173, 12323644827160494, 1341444755814814815, 145254565866802469136

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OFFSET

1,2

LINKS

Table of n, a(n) for n=1..15.

MAPLE

conca := proc(S) local resul, d, i ; resul := 0 ; for i from 1 to nops(S) do d := ilog10(op(i, S))+1 ; resul := resul*10^d+op(i, S) ; od ; resul ; end: A081542 := proc(row) local a, p, i; if row =1 then RETURN(0) ; fi ; a := [] ; p := [seq(row+1-i, i=1..row)] ; for i from 1 to row do a := [op(a), conca(subsop(i=NULL, p))] ; od: add(op(i, a), i=1..row) ; end: seq(op(A081542(n)), n=1..15) ; # R. J. Mathar, Jul 15 2007

CROSSREFS

Cf. A081539, A081540, A081541.

Cf. A081541.

Sequence in context: A166241 A140158 A160875 * A160877 A160880 A261008

Adjacent sequences: A081539 A081540 A081541 * A081543 A081544 A081545

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy, Mar 29 2003

EXTENSIONS

Needs editing - see A081539, A081540 for a model. - N. J. A. Sloane

More terms from R. J. Mathar, Jul 15 2007

STATUS

approved