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A145397 Numbers not of the form 1/6*m*(m+1)*(m+2), the non-tetrahedral numbers. 6
2, 3, 5, 6, 7, 8, 9, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Complement of A000292; A000040 is a subsequence;

A014306(a(n)) = 1; A023533(a(n)) = 0.

LINKS

Table of n, a(n) for n=1..72.

Cristinel Mortici, Remarks on Complementary Sequences, Fibonacci Quart. 48 (2010), no. 4, 343-347.

PROG

(PARI) is(n)=binomial(sqrtnint(6*n, 3)+2, 3)!=n \\ Charles R Greathouse IV, Feb 22 2017

CROSSREFS

Sequence in context: A268231 A039167 A247360 * A183570 A181092 A184526

Adjacent sequences:  A145394 A145395 A145396 * A145398 A145399 A145400

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Oct 14 2008

EXTENSIONS

Definition corrected by Ant King, Sep 20 2012

STATUS

approved

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Last modified May 28 10:48 EDT 2017. Contains 287240 sequences.