A182539 - OEIS

A182539

a(n) = a(n-1) + (a(n-2) AND n).

0, 1, 1, 2, 2, 2, 4, 6, 6, 6, 8, 10, 18, 26, 28, 38, 54, 54, 72, 90, 90, 106, 124, 126, 150, 174, 192, 202, 202, 210, 220, 238, 238, 270, 304, 306, 338, 370, 372, 406, 438, 438, 472, 506, 514, 554, 556, 598, 630, 646, 696, 698, 746, 794, 828, 846, 902, 910, 912, 922, 938, 962, 1004, 1006, 1070

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OFFSET

0,4

LINKS

Table of n, a(n) for n=0..64.

FORMULA

a(0)=0, a(1)=1, a(n) = a(n-1) + (a(n-2) AND n), where AND is the bitwise AND operator.

MATHEMATICA

RecurrenceTable[{a[0]==0, a[1]==1, a[n]==a[n-1]+BitAnd[a[n-2], n]}, a, {n, 70}] (* Harvey P. Dale, Jan 23 2013 *)

PROG

(Python)

prpr, prev = 0, 1