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A073512 Number of primes less than 10^n with initial digit 6. 0
0, 2, 18, 135, 1013, 8458, 72257, 628206, 5556434, 49815418, 451476802, 4128049326, 38024311091, 352446754137, 3284400373590, 30749731897370, 289066731934716, 2727216210298152, 25812680778645432 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

LINKS

Thomas R. Nicely, Some Results of Computational Research in Prime Numbers

EXAMPLE

a(2)=2 because there are 2 primes up to 10^2 whose initial digit is 2 (namely 61 and 67).

MATHEMATICA

f[n_] := f[n] = PrimePi[7*10^n] - PrimePi[6*10^n] + f[n - 1]; f[0] = 0; Table[ f[n], {n, 0, 12}]

CROSSREFS

Cf. A073509 to A073517, their sum is A006880.

Sequence in context: A064447 A043022 A057971 * A005544 A154636 A193446

Adjacent sequences:  A073509 A073510 A073511 * A073513 A073514 A073515

KEYWORD

base,hard,nonn

AUTHOR

Shyam Sunder Gupta (guptass(AT)rediffmail.com), Aug 14 2002

EXTENSIONS

Edited and extended by Robert G. Wilson v (rgwv(AT)rgwv.com), Aug 29 2002

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Last modified February 17 14:50 EST 2012. Contains 206050 sequences.