

A233394


Sum of cdivisors of n.


3



1, 2, 4, 4, 8, 9, 11, 8, 14, 12, 22, 17, 27, 26, 26, 16, 26, 24, 36, 26, 39, 36, 52, 33, 51, 45, 68, 48, 73, 63, 57, 32, 50, 44, 64, 40, 67, 60, 82, 50, 77, 54, 96, 68, 94, 88, 114, 65, 99, 87, 124, 85, 124, 103, 153, 92, 139, 120, 170, 115, 171, 140, 120, 64
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OFFSET

1,2


LINKS

Peter J. C. Moses, Table of n, a(n) for n = 1..5000
Index entries for sequences related to binary expansion of n


EXAMPLE

Let n=23. By the definition of cdivisor (see comment in A124771), 23 has the following cdivisors: 0, 1, 2, 3, 5, 7, 11, 23. So a(23)=52.


MATHEMATICA

bitPatt[n_]:=bitPatt[n]=Split[IntegerDigits[n, 2], #1>#2#2==0&]; cDivisors[0]:={0}; cDivisors[n_]:=Insert[Insert[Map[#[[1]]&, Select[Table[{z, Cases[{bitPatt[n]}, Apply[{___, ##, ___}&, bitPatt[z]]]}, {z, n/2}], #[[2]]=!={}&]], 0, 1], n, 1]; Map[Apply[Plus, cDivisors[#]]&, Range[50]] (* Peter J. C. Moses, Dec 08 2013 *)


CROSSREFS

Cf. A114994, A124771.
Sequence in context: A285273 A188824 A181212 * A029599 A213064 A076466
Adjacent sequences: A233391 A233392 A233393 * A233395 A233396 A233397


KEYWORD

nonn,base


AUTHOR

Vladimir Shevelev, Dec 08 2013


EXTENSIONS

More terms from Peter J. C. Moses, Dec 08 2013


STATUS

approved



