A073260 - OEIS

A073260

Length of FixedPointList leading to value of [10^n]-th composite number.

4, 4, 4, 5, 5, 6, 7, 7, 7, 8, 8, 9, 9

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

One plus the number of iterations necessary to reach the composite number using the formula in the program. - Robert G. Wilson v, Jul 23 2002

LINKS

Table of n, a(n) for n=1..13.

FORMULA

See program below.

EXAMPLE

n=10^11: the list= {100000000000, 104118054814, 104280509328, 104286914053, 104287166025, 104287176027, 104287176414, 104287176419}, its length including initial term is 8, so a(11)=8.

MATHEMATICA

Table[Length[FixedPointList[10^w+PrimePi[ # ]+1&, 10^w]]-1, {w, 1, 11}]

CROSSREFS

Cf. A064814, A065857, A002808, A073255-A073264.

Sequence in context: A369339 A368868 A134992 * A350459 A036854 A036858

Adjacent sequences: A073257 A073258 A073259 * A073261 A073262 A073263

KEYWORD

nonn,more

AUTHOR

Labos Elemer, Jul 22 2002

EXTENSIONS

More terms from Robert G. Wilson v, Jul 23 2002

STATUS

approved