Recent sequences lacking keyword "base"

FRANCISCO SALINAS franciscodesalinas at hotmail.com
Fri Oct 6 00:28:18 CEST 2006


Klaus, and what about these not so recent ones?:

A117807  Start with 1015 and repeatedly reverse the digits and add 4 to get 
the next term.
A079130  Primes such that iterated sum-of-digits (A038194) is a square.
A079131  Primes such that iterated sum-of-digits (A038194) is odd.
A079132  Primes such that iterated sum-of-digits (A038194) is even.

....and many more indeed.

Any objections?

Thanks.


>From: Klaus Brockhaus <klaus-brockhaus at t-online.de>
>To: seqfan <seqfan at ext.jussieu.fr>
>Subject: Recent sequences lacking keyword "base"
>Date: Thu, 05 Oct 2006 20:08:06 +0200
>
>
>A123179 a(1)=1 a(2)=121, and a(n)=a(n-1) n 2 n 3 n ... n (n-1) n 1, using 
>concatenation.
>A123171 a(1) = 123, a(n) = sum of digits of all previous terms.
>A123157 Sum of digits of the squares of prime numbers.
>A123153 a(n) = nth digit of Pi times the nth prime number. (?)
>A123152 Digits of Pi + 1. (?)
>A123139 a(n) = prime(n)*(prime(n+1)+1) - (n^3+ sum of digits of n^3).
>A123138 The nth digit of a(n-1) gives the position of digit n in a(n), 
>a(1)=263514.
>A123137 a(n) = a(n-1)^2 + Sum of the digits of a(n-1), a(1)=1.
>A123135 a(n) = n^3 plus sum of digits of n^3.
>
>... and maybe some more. Any objections?
>
>Thanks, Klaus.








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