Json::Array debug_accountRangeAt(string _blockHashOrNumber, int _txIndex, string _addressHash, int _maxResults)

Get the list of accounts of size _maxResults in the given _blockHashOrNumber after given _txIndex. AddressMap contains addressHash - > address starting from given _addressHash.
nexKey field is the next addressHash (if any addresses left in the state).

The return is like

{
    "addressMap" : {
        "036014....109616b" : "a94f5374fce5edbc8e2a8697c15331677e6ebf0b",
        "0fbc62.....ba962a6" : "095e7baea6a6c7c4c2dfeb977efac326af552d87"
    },
    "nextKey" : "0000000000000000000000000000000000000000000000000000000000000000"
}

Allows to select range of accounts in given block number or hash after _txIndex.