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A105388 Number of divisors of concatenated even numbers. 1
2, 8, 8, 6, 32, 12, 4, 48, 96, 48, 8, 40, 64, 24, 32, 32, 12, 96, 16, 448, 64, 48, 256, 16, 192, 36, 24, 640, 32, 192, 16, 32, 256, 72, 256, 288, 16, 384, 256, 256, 32, 12, 128, 60, 160, 1536, 2048, 64, 16, 2304, 64, 64, 96, 72, 32, 48, 512, 24, 256, 1536, 64, 72, 768, 40, 4096, 48, 16, 512, 1024 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..68.

EXAMPLE

The number of divisors of 24 is 8 - which is the second term.

The number of divisors of 246 is 8 - which is the third term.

The number of divisors of 2468 is 6 - which is the fourth term.

MATHEMATICA

Table[DivisorSigma[0, FromDigits[Flatten[IntegerDigits/@(2Range[n])]]], {n, 30}] (* Harvey P. Dale, Dec 10 2016 *)

CROSSREFS

Cf. A019520, A108728 (number of distinct prime divisors).

Sequence in context: A198367 A021780 A020769 * A178247 A048651 A243596

Adjacent sequences:  A105385 A105386 A105387 * A105389 A105390 A105391

KEYWORD

base,nonn

AUTHOR

Parthasarathy Nambi, Apr 30 2005

EXTENSIONS

More terms from Harvey P. Dale, Dec 10 2016

a(30)-a(69) from Michael S. Branicky, Feb 08 2021 (computed using prime factorizations linked in A108728)

STATUS

approved

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Last modified March 6 12:03 EST 2021. Contains 341847 sequences. (Running on oeis4.)