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A057573 Number of primes in A051351 which have index <= 10^n. 1
1, 7, 25, 122, 934, 7268, 61756, 537324, 4756645 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..9.

Index entries for sequences related to numbers of primes in various ranges

MATHEMATICA

NextPrime[ n_Integer ] := Module[ {k}, k = n + 1; While[ ! PrimeQ[ k ], k++ ]; k ]; c = d = p = q = 0; Do[ While[ d++; d <= 10^n, q = NextPrime[ q ]; p = p + Apply[ Plus, RealDigits[ q ] [[ 1 ] ]]; If[ PrimeQ[ p ], c++ ]]; d--; Print[ c ], {n, 0, 10} ]

CROSSREFS

Cf. A051351 and A058049.

Sequence in context: A141626 A138292 A138738 * A082651 A241714 A151491

Adjacent sequences:  A057570 A057571 A057572 * A057574 A057575 A057576

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Nov 27 2000

STATUS

approved

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Last modified February 25 05:11 EST 2020. Contains 332217 sequences. (Running on oeis4.)