login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A175038 In the sequence of positive integers A000027, number of digits between successive primes. 2

%I #38 Feb 07 2019 12:59:18

%S 0,1,1,4,2,6,2,6,10,2,10,6,2,6,10,10,2,10,6,2,10,6,10,14,7,3,9,3,9,39,

%T 9,15,3,27,3,15,15,9,15,15,3,27,3,9,3,33,33,9,3,9,15,3,27,15,15,15,3,

%U 15,9,3,27,39,9,3,9,39,15,27,3,9,15,21,15,15,9,15,21,9,21,27,3,27,3,15,9,15

%N In the sequence of positive integers A000027, number of digits between successive primes.

%C From _Jamie Morken_, Feb 01 2019: (Start)

%C For A006880(m) < n < A006880(m+1), a(n) = A046933(n)*(m + 1).

%C For example m=1, n=24 then a(n)=7*2=14.

%C For example m=2, n=26 then a(n)=1*3=3.

%C For n = A006880(m+1), a(n) = A046933(n)*(m+1) + A033873(m + 1).

%C For example m=1, n=25 then a(n)=3*2+1=7.

%C (End)

%H Muniru A Asiru, <a href="/A175038/b175038.txt">Table of n, a(n) for n = 1..10000</a>

%e a(4) = 4 as prime(4) = 7 and prime(4+1) = 11 so the number of digits between these two primes is the number of digits of 8, 9 and 10. These numbers have 4 digits combined. Therefore a(4) = 4. - _David A. Corneth_, Jan 30 2019

%t Table[Length[Flatten[IntegerDigits/@Range[Prime[n]+1,Prime[n+1]-1]]],{n,200}]

%o (PARI) a(n) = sum(k=prime(n)+1, prime(n+1)-1, #Str(k)); \\ _Michel Marcus_, Jan 30 2019

%Y Cf. A000027, A113610, A046933, A006880, A033873.

%K base,nonn

%O 1,4

%A _Zak Seidov_, Nov 13 2009

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 25 11:36 EDT 2024. Contains 371968 sequences. (Running on oeis4.)