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A135326 Sum of all n-digit terms of A005043. 0
12, 142, 835, 5798, 124932, 853467, 6536382, 50852019, 1234849644, 9043402501, 73007772802, 593742784829, 4859761676391, 125320157443726, 953467954114363, 7939655757745265, 66368199913921497, 556704809728838604, 4684478925507420069, 125076091920076709793 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..20.

EXAMPLE

Sum of all 1-digit Riordan numbers is 1 + 0 + 1 + 1 + 3 + 6 = 12.

Sum of all 2-digit Riordan numbers is 15 + 36 + 91 = 142.

Sum of all 3-digit Riordan numbers is 232 + 603 = 835.

MATHEMATICA

digNum[n_] := Length @ IntegerDigits[n]; rio[0] = 1; rio[1] = 0; rio[n_] := rio[n] = (n - 1)*(2*rio[n - 1] + 3*rio[n - 2])/(n + 1); digCount = 0; sum = 0; cumsum = {}; Do[r = rio[n]; If[digNum[r] > digCount, digCount++; AppendTo[cumsum, sum]]; sum += r, {n, 0, 50}]; Differences[cumsum] (* Amiram Eldar, Nov 30 2019 *)

CROSSREFS

Cf. A005043.

Sequence in context: A124206 A061636 A266177 * A056340 A056330 A158516

Adjacent sequences:  A135323 A135324 A135325 * A135327 A135328 A135329

KEYWORD

nonn,base,less

AUTHOR

Parthasarathy Nambi, Dec 06 2007

EXTENSIONS

More terms from Amiram Eldar, Nov 30 2019

STATUS

approved

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Last modified August 13 22:57 EDT 2020. Contains 336473 sequences. (Running on oeis4.)