K (ngn/k), 19 bytes

{+//(64#2)\'x_!1+y}

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{ } is a function with arguments x and y

!1+y is the list 0 1 ... y

x_ drops the first x elements

64#2 is the list 2 2 ... 2 (64 times)

(64#2)\' encodes each int as a list of 64 binary digits

+/ sum

+// sum until convergence; in this case sum of the sum of all binary digit lists

K (ngn/k), 19 13 bytes

{+//2\x_!1+y}

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{ } is a function with arguments x and y

!1+y is the list 0 1 ... y

x_ drops the first x elements

2\ encodes each int as a list of binary digits of the same length (this is specific to ngn/k)

+/ sum

+// sum until convergence; in this case sum of the sum of all binary digit lists

K (ngn/k), 19 bytes

{+//(64#2)\'x_!1+y}

Try it online!

K (ngn/k), 19 bytes

{+//(64#2)\'x_!1+y}

Try it online!

{ } is a function with arguments x and y

!1+y is the list 0 1 ... y

x_ drops the first x elements

64#2 is the list 2 2 ... 2 (64 times)

(64#2)\' encodes each int as a list of 64 binary digits

+/ sum

+// sum until convergence; in this case sum of the sum of all binary digit lists