cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A361170 The leading column of the table of primes in the top row and subsequent rows defined by the GPF of Pascal-alike sums of previous rows.

Original entry on oeis.org

2, 5, 7, 3, 5, 5, 3, 2, 3, 3, 2, 7, 3, 2, 7, 3, 5, 2, 7, 3, 5, 3, 5, 5, 3, 2, 7, 7, 7, 5, 7, 5, 2, 7, 7, 3, 5, 7, 3, 2, 2, 2, 2, 7, 3, 5, 3, 3, 2, 3, 2, 2, 3, 2, 7, 3, 2, 7, 7, 5, 5, 7, 3, 2, 3, 3, 2, 5, 2, 7, 7, 3, 5, 3, 2, 2, 2, 2, 5, 2, 2, 3, 3, 2, 2, 2, 2, 5, 5, 2, 2, 3, 2, 2
Offset: 1

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Author

R. J. Mathar, May 10 2023

Keywords

Examples

			The table starts
  2  3  5  7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71
  5  2  3  3  3  5  3  7 13  5 17 13  7  5  5  7  5  2 23  3
  7  5  3  3  2  2  5  5  3 11  5  5  3  5  3  3  7  5 13 11
  3  2  3  5  2  7  5  2  7  2  5  2  2  2  3  5  3  3  3 11
  5  5  2  7  3  3  7  3  3  7  7  2  2  5  2  2  3  3  7  7
  5  7  3  5  3  5  5  3  5  7  3  2  7  7  2  5  3  5  7  3
  3  5  2  2  2  5  2  2  3  5  5  3  7  3  7  2  2  3  5  2
  2  7  2  2  7  7  2  5  2  5  2  5  5  5  3  2  5  2  7  5
		

Crossrefs

Cf. A006530, A071216 (row n=2).

Programs

  • Maple
    T361170 := proc(n,k)
        option remember ;
        if n = 1 then
            ithprime(k) ;
        else
            A006530(procname(n-1,k+1)+procname(n-1,k)) ;
        end if;
    end proc:
    A361170 := proc(n)
        T361170(n,1) ;
    end proc:
    seq(A361170(n),n=1..120) ;

Formula

a(n) = T(n,1) where T(1,k) = prime(k), T(n,k) = A006530( T(n-1,k+1) + T(n-1,k)).