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A069172 Smallest triangular number such that arithmetic mean of its digits = n (sum of the digits = n times the number of digits). 0
1, 105, 3, 435, 28, 6, 5995, 589598998999878 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Because A045914 is complete, this sequence is complete. - Robert G. Wilson v, Oct 30 2013

LINKS

Table of n, a(n) for n=1..8.

MATHEMATICA

Do[k = 1; While[ Apply[ Plus, IntegerDigits[k(k + 1)/2]] != n*Floor[ Log[10, k(k + 1)/2] + 1], k++ ]; Print[k(k + 1)/2], {n, 1, 7}]

CROSSREFS

Cf. A069790.

Sequence in context: A157874 A282188 A271764 * A231578 A104437 A112814

Adjacent sequences:  A069169 A069170 A069171 * A069173 A069174 A069175

KEYWORD

base,fini,full,nonn

AUTHOR

Robert G. Wilson v, Apr 09 2002

EXTENSIONS

a(8) from Donovan Johnson, Mar 30 2010

STATUS

approved

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Last modified November 26 03:20 EST 2020. Contains 338632 sequences. (Running on oeis4.)