During which blocks did the DDos attack create millions of empty accounts?

Question

This post (Why were empty accounts allowed to be on the blockchain?) discusses the Ddos attack from fall 2016. It mentions that nearly 20,000,000 account were created and then immediately deleted causing a huge bloat in the state trie. Does anyone know during which blocks those Ddos attacks were created?

If one were to ever try to create an index of accounts, that index would become unnecassarily bogged down. If one knew during which blocks they were created, one could simply skip these accounts given that they would be deleted soon thereafter by the hard fork.

Answer 1

From Why is my node synchronization stuck/extremely slow at block 2,306,843?:

2,421,507 to 2,463,130 - Account bloat transactions where 19 million empty accounts were created. This causes the node clients to slow down as the many accounts cannot be kept in cache requiring slow re-retrieval from disk.

From Ethereum Network Attacker’s IP Address Is Traceable, there were two contracts deployed to execute this attack:

• 0x6a0a0fc761c612c340a0e98d33b37a75e5268472 created in block #2,421,490 with the first transaction in block #2,421,507 and the last transaction in block #2,435,148.

• 0x7c20218efc2e07c8fe2532ff860d4a5d8287cb31 created in block #2,423,558 with the first transaction in block #2,423,577 and the last transaction in block #2,463,130.