The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A174947 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A174947

Triangle read by rows: T(n,k) = (prime(n)+1) mod prime(k).
(history; published version)

#19 by OEIS Server at Fri Apr 12 17:42:53 EDT 2024

LINKS

G. C. Greubel, <a href="/A174947/b174947_1.txt">Rows n = 1..50 of the triangle, flattened</a>

#18 by Alois P. Heinz at Fri Apr 12 17:42:52 EDT 2024

STATUS

proposed

approved

Discussion

Fri Apr 12

17:42

OEIS Server: Installed first b-file as b174947.txt.

#17 by Michel Marcus at Fri Apr 12 17:31:06 EDT 2024

STATUS

editing

proposed

#16 by Michel Marcus at Fri Apr 12 17:31:03 EDT 2024

PROG

(PARI) trga(nrows) = {for (n=1, nrows, for (k=1, n, print1(sigma(prime(n)) % prime(k), ", "); ); print(); ); } \\ Michel Marcus, Apr 11 2013

STATUS

proposed

editing

#15 by G. C. Greubel at Fri Apr 12 16:50:46 EDT 2024

STATUS

editing

proposed

#14 by G. C. Greubel at Fri Apr 12 16:50:43 EDT 2024

CROSSREFS

Cf. A174428, A173655, A173662, A174996, A175620, A177226.

#13 by G. C. Greubel at Wed Apr 10 23:54:41 EDT 2024

NAME

Triangle read by rows: RT(n,k) = (prime(n)+1) mod prime(k).

DATA

1, 0, 1, 0, 0, 1, 0, 2, 3, 1, 0, 0, 2, 5, 1, 0, 2, 4, 0, 3, 1, 0, 0, 3, 4, 7, 5, 1, 0, 2, 0, 6, 9, 7, 3, 1, 0, 0, 4, 3, 2, 11, 7, 5, 1, 0, 0, 0, 2, 8, 4, 13, 11, 7, 1, 0, 2, 2, 4, 10, 6, 15, 13, 9, 3, 1, 0, 2, 3, 3, 5, 12, 4, 0, 15, 9, 7, 1, 0, 0, 2, 0, 9, 3, 8, 4, 19, 13, 11, 5, 1, 0, 2, 4, 2, 0, 5, 10, 6, 21, 15, 13, 7, 3, 1

COMMENTS

Triangle read by rows: RT(n,k) = Sigma(prime(n)) mod prime(k), where Sigma(prime(.)) is the sum of divisors of prime.

LINKS

G. C. Greubel, <a href="/A174947/b174947_1.txt">Rows n = 1..50 of the triangle, flattened</a>

EXAMPLE

1;

0, 1;

0, 0, 1;

0, 2, 3, 1;

0, 0, 2, 5, 1;

0, 2, 4, 0, 3, 1;

0, 0, 3, 4, 7, 5, 1;

0, 2, 0, 6, 9, 7, 3, 1;

0, 0, 4, 3, 2, 11, 7, 5, 1;

0, 0, 0, 2, 8, 4, 13, 11, 7, 1;

MATHEMATICA

Table[Mod[1+Prime[n], Prime[k]], {n, 15}, {k, n}]//Flatten (* G. C. Greubel, Apr 10 2024 *)

PROG

(Magma)

[(1+NthPrime(n)) mod NthPrime(k): k in [1..n], n in [1..15]]; // G. C. Greubel, Apr 10 2024

(SageMath)

flatten([[(1+nth_prime(n))%nth_prime(k) for k in range(1, n+1)] for n in range(1, 16)]) # G. C. Greubel, Apr 10 2024

STATUS

approved

editing

#12 by Bruno Berselli at Thu Apr 11 02:58:15 EDT 2013

STATUS

proposed

approved

#11 by Michel Marcus at Thu Apr 11 01:38:50 EDT 2013

STATUS

editing

proposed

#10 by Michel Marcus at Thu Apr 11 01:38:30 EDT 2013

EXAMPLE

Triangle begins

1;

0, 1;

0, 0, 1;

0, 2, 3, 1;

0, 0, 2, 5, 1;

PROG

(PARI)trga(nrows) = {for (n=1, nrows, for (k=1, n, print1(sigma(prime(n)) % prime(k), ", "); ); print(); ); } \\ Michel Marcus, Apr 11 2013

KEYWORD

nonn,tabl

STATUS

approved

editing