login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A106116 Primes with smallest digit > 1. 7
2, 3, 5, 7, 23, 29, 37, 43, 47, 53, 59, 67, 73, 79, 83, 89, 97, 223, 227, 229, 233, 239, 257, 263, 269, 277, 283, 293, 337, 347, 349, 353, 359, 367, 373, 379, 383, 389, 397, 433, 439, 443, 449, 457, 463, 467, 479, 487, 499, 523, 547, 557, 563, 569, 577, 587, 593 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Subsequence of A038603 - Jonathan Vos Post, Feb 10 2010

LINKS

Indranil Ghosh, Table of n, a(n) for n = 1..50000

Chris C. Caldwell, Yarborough prime

James Maynard, Primes with restricted digits, arXiv:1604.01041 [math.NT], 2016.

James Maynard and Brady Haran, Primes without a 7, Numberphile video (2019)

FORMULA

a(n) >> n^k with k = log 10/log 8 = 1.107.... - Charles R Greathouse IV, Jan 02 2013

MATHEMATICA

Select[Prime[Range[100]], Min[IntegerDigits[ # ]]>1&]

PROG

(PARI) is(p)=vecsort(digits(p), , 8)[1]>1 && isprime(p) \\ Charles R Greathouse IV, Jan 02 2013

CROSSREFS

Cf. A000040, A038603, A106745.

Sequence in context: A320585 A024770 A038603 * A091727 A240920 A030144

Adjacent sequences:  A106113 A106114 A106115 * A106117 A106118 A106119

KEYWORD

nonn,base

AUTHOR

Zak Seidov, May 07 2005

EXTENSIONS

Terms > 523 added by Jonathan Vos Post, Feb 10 2010

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified February 17 18:14 EST 2020. Contains 332005 sequences. (Running on oeis4.)