142

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Number

$142$ (one hundred and forty-two) is:

$2 \times 71$


The $18$th nontotient after $14$, $26$, $34$, $38$, $50$, $62$, $68$, $74$, $76$, $86$, $90$, $94$, $98$, $114$, $118$, $122$, $124$, $134$:
$\nexists m \in \Z_{>0}: \map \phi m = 142$
where $\map \phi m$ denotes the Euler $\phi$ function


The $59$th positive integer after $2$, $3$, $4$, $7$, $8$, $\ldots$, $95$, $96$, $100$, $101$, $102$, $107$, $112$, $116$, $124$, $136$, $137$, $141$ which cannot be expressed as the sum of distinct pentagonal numbers.


Also see