3160

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Number

$3160$ (three thousand, one hundred and sixty) is:

$2^3 \times 5 \times 79$


The $40$th hexagonal number after $1$, $6$, $15$, $28$, $45$, $66$, $91$, $\ldots$, $2145$, $2278$, $2415$, $2556$, $2701$, $2850$, $3003$:
$3160 = \ds \sum_{k \mathop = 1}^{40} \paren {4 k - 3} = 40 \paren {2 \times 40 - 1}$


The $79$th triangular number after $1$, $3$, $6$, $10$, $15$, $\ldots$, $2701$, $2775$, $2850$, $2926$, $3003$, $3081$:
$3160 = \ds \sum_{k \mathop = 1}^{79} k = \dfrac {79 \times \paren {79 + 1} } 2$


Also see