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A095408 Total number of decimal digits in all distinct prime factors of n minus number of digits of n. 3
-1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, 0, 0, 0, 0, 0, 1, 0, 0, -1, 1, -1, 0, 0, 1, 0, -1, 1, 1, 0, 0, 0, 1, 1, 0, 0, 1, 0, 1, 0, 1, 0, 0, -1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, -1, 1, 2, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 2, 0, 0, -1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, -1, 0, 1, 0, 0, 0, 0, 0, -1, 0, 1, 0, -1, 0, 1, 0, 0, 0, 0, 0, 0, -1 (list; graph; refs; listen; history; internal format)
OFFSET

1,66

FORMULA

a[n]=A095407[n]-A055642[n]

EXAMPLE

n=22: prime set={2,11}, a[22]=3-2=1;

n=63: prime set={3,7}, a[63]=2-2=0;

n=100: prime set={2,5}, a[100]=2-3=-1.

MATHEMATICA

ffi[x_] :=Flatten[FactorInteger[x]] lf[x_] :=Length[FactorInteger[x]] ba[x_] :=Table[Part[ffi[x], 2*j-1], {j, 1, lf[x]}] tdp[x_] :=Flatten[Table[IntegerDigits[Part[ba[x], j]], {j, 1, lf[x]}], 1] pl[x_] :=Length[tdp[x]] nl[x_] :=Length[IntegerDigits[x]] t1=Table[nl[w], {w, 1, 1000}]; t2=Table[pl[w], {w, 1, 1000}]; t2-t1

CROSSREFS

Cf. A055642, A095407.

Sequence in context: A185249 A075107 A178498 * A133008 A102550 A116929

Adjacent sequences:  A095405 A095406 A095407 * A095409 A095410 A095411

KEYWORD

base,sign

AUTHOR

Labos E. (labos(AT)ana.sote.hu), Jun 21 2004

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Last modified February 16 20:14 EST 2012. Contains 205962 sequences.