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A107583 a(n) = 3^n - 3*n. 11
1, 0, 3, 18, 69, 228, 711, 2166, 6537, 19656, 59019, 177114, 531405, 1594284, 4782927, 14348862, 43046673, 129140112, 387420435, 1162261410, 3486784341 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

a(n) is the number k such that the number m with n 3's and k 1's has digit product = digit sum = 3^n.

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

EXAMPLE

Corresponding numbers m are 1, 3, 11133, 111111111111111111333, ...

MATHEMATICA

Table[3^m-3*m, {m, 0, 20}]

PROG

(MAGMA) [3^n-3*n: n in [0..30]]; // Vincenzo Librandi, Oct 22 2011

(PARI) a(n)=3^n-3*n \\ Charles R Greathouse IV, Sep 08 2012

CROSSREFS

Cf. A107584, A107585.

Sequence in context: A027333 A026576 A048899 * A157535 A098522 A174764

Adjacent sequences:  A107580 A107581 A107582 * A107584 A107585 A107586

KEYWORD

nonn,easy

AUTHOR

Zak Seidov, May 16 2005

EXTENSIONS

Corrected by Charles R Greathouse IV, Sep 08 2012

STATUS

approved

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Last modified October 17 11:57 EDT 2019. Contains 328109 sequences. (Running on oeis4.)