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A113796 Numbers n such that n=T(x)+T(y) where T(k) is the k-th triangular number and n is x concatenated y in base 10. 0
190, 191, 19900, 19901, 90415, 585910, 1201545, 1414910, 1501726, 1909415, 1999000, 1999001, 2442196, 7003676, 7693846, 14745226, 28296970, 30307171, 42009156, 47748526, 61549231, 63249300, 78049756, 82749850, 84559880 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..25.

EXAMPLE

90415=T(90)+T(415)

MATHEMATICA

lst = {}; t[n_] := n(n + 1)/2; Do[p=10; While[n > p, If[t[Mod[n, p]] + t[Floor[n/p]] == n, AppendTo[lst, n]]; p*= 10], {n, 10^6}]; lst

CROSSREFS

Sequence in context: A118878 A036208 A119903 * A127994 A025391 A025382

Adjacent sequences:  A113793 A113794 A113795 * A113797 A113798 A113799

KEYWORD

base,nonn

AUTHOR

Giovanni Resta, Jan 21 2006

STATUS

approved

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Last modified March 29 05:39 EDT 2020. Contains 333105 sequences. (Running on oeis4.)