Strong's numbers

תּוֹלְדָה H8435

tôwlᵉdâh

to-led-aw'

or תֹּלְדָה; from יָלַד; (plural only) descent, i.e. family; (figuratively) history; birth, generations.

[תּוֹלֵדוֹת] 39 n.f.pl. generations, esp. in genealogies = account of a man and his descendants

From Brown, Driver, and Briggs, A Hebrew and English Lexicon of the Old Testament (1906), in the public domain.

Shown in the King James Version (KJV), whichever translation you read in — it is the text these numbers are tagged against.

Genesis 2:4
These are the generations of the heavens and of the earth when they were created, in the day that the LORD God made the earth and the heavens,
Genesis 5:1
This is the book of the generations of Adam. In the day that God created man, in the likeness of God made he him;
Genesis 6:9
These are the generations of Noah: Noah was a just man and perfect in his generations, and Noah walked with God.
Genesis 10:1
Now these are the generations of the sons of Noah, Shem, Ham, and Japheth: and unto them were sons born after the flood.
Genesis 10:32
These are the families of the sons of Noah, after their generations, in their nations: and by these were the nations divided in the earth after the flood.
Genesis 11:10
These are the generations of Shem: Shem was an hundred years old, and begat Arphaxad two years after the flood:
Genesis 11:27
Now these are the generations of Terah: Terah begat Abram, Nahor, and Haran; and Haran begat Lot.
Genesis 25:12
Now these are the generations of Ishmael, Abraham's son, whom Hagar the Egyptian, Sarah's handmaid, bare unto Abraham:
Genesis 25:13
And these are the names of the sons of Ishmael, by their names, according to their generations: the firstborn of Ishmael, Nebajoth; and Kedar, and Adbeel, and Mibsam,
Genesis 25:19
And these are the generations of Isaac, Abraham's son: Abraham begat Isaac: