This site is supported by donations to The OEIS Foundation.

# 39

Please do not rely on any information it contains.

39 is an integer.

## Membership in core sequences

 Odd numbers ..., 33, 35, 37, 39, 41, 43, 45, ... A005843 Semiprimes ..., 34, 35, 38, 39, 46, 49, 51, ... A001358 Composite numbers ..., 35, 36, 38, 39, 40, 42, 44, ... A002808 Deficient numbers ..., 35, 37, 38, 39, 41, 43, 44, ... A005100 Squarefree numbers ..., 35, 37, 38, 39, 41, 42, 43, ... A005117

## Sequences pertaining to 39

 Multiples of 39 0, 39, 78, 117, 156, 195, 234, 273, 312, 351, 390, 429, 468, ... ${\displaystyle 3x+1}$ sequence starting at 39 39, 118, 59, 178, 89, 268, 134, 67, 202, 101, 304, 152, 76, 38, ... A008878 Fermat pseudoprimes to base 39 38, 95, 133, 341, 1561, 1834, 1891, 2047, 2101, 2465, 3053, 3439, ... A020167

PLACEHOLDER

PLACEHOLDER

REMARKS

TABLE

TABLE GOES HERE

## Factorization of some small integers in a quadratic integer ring adjoining the square roots of −39, 39

REMARKS GO HERE

TABLE GOES HERE

MORE REMARKS

FACTORIZATION OF IDEALS

PLACEHOLDER

TABLE GOES HERE

## Representation of 39 in various bases

 Base 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Representation 100111 1101 211 122 101 52 47 41 39 34 31 2B 29 27 27 23 21 1I 1J

In base 10, we see that 39 is the smallest number of multiplicative persistence 3, since 3 × 9 = 27, 2 × 7 = 14 and 1 × 4 = 4.

 ${\displaystyle -1}$ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 1729