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Revision History for A138963

(Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
Showing entries 1-10 | older changes

A138963

a(1) = 1, a(n) = the largest prime divisor of A138793(n).
(history; published version)

#24 by Michael De Vlieger at Thu May 26 09:52:25 EDT 2022

STATUS

reviewed

approved

#23 by Joerg Arndt at Thu May 26 09:52:21 EDT 2022

STATUS

proposed

reviewed

#22 by Michel Marcus at Thu May 26 08:39:37 EDT 2022

STATUS

editing

proposed

#21 by Michel Marcus at Thu May 26 08:39:25 EDT 2022

CROSSREFS

Cf. A006530, A138793, A138962.

Cf. A104759, A000422, A116504, A007908, A116505, A104759, A075019, A075020, A075021, A075022, A138789, A138790, A138958, A138959, A138960, A138962.

STATUS

approved

editing

#20 by OEIS Server at Thu May 26 08:38:25 EDT 2022

LINKS

Daniel Suteu and Robert Price, <a href="/A138963/b138963_1.txt">Table of n, a(n) for n = 1..63</a> (terms a(1)..a(45) from Robert Price)

#19 by Michel Marcus at Thu May 26 08:38:25 EDT 2022

STATUS

reviewed

approved

Discussion

Thu May 26

08:38

OEIS Server: Installed new b-file as b138963.txt.  Old b-file is now b138963_1.txt.

#18 by Joerg Arndt at Thu May 26 07:52:19 EDT 2022

STATUS

proposed

reviewed

#17 by Daniel Suteu at Thu May 26 07:34:44 EDT 2022

STATUS

editing

proposed

#16 by Daniel Suteu at Thu May 26 07:32:34 EDT 2022

PROG

(PARI)

(PARI)f(n) = my(D = Vec(concat(apply(s->Str(s), [1..n])))); eval(concat(vector(#D, k, D[#D-k+1]))); \\ A138793

#15 by Daniel Suteu at Thu May 26 07:31:40 EDT 2022

NAME

a(1) = 1; , a(n+1) = the largest prime divisor of A138793(n+1).

DATA

1, 7, 107, 149, 953, 218107, 402859, 4877, 379721, 4349353, 169373, 182473, 1940144339383, 2184641, 437064932281, 5136696159619, 67580875919190833, 1156764458711, 464994193118899, 4617931439293, 1277512103328491957510030561, 8177269604099

LINKS

Daniel Suteu and Robert Price, <a href="/A138963/b138963_1.txt">Table of n, a(n) for n = 1..63</a> (terms a(1)..a(45</a>) from Robert Price)

FORMULA

a(n) = A006530(A138793(n)). - Daniel Suteu, May 26 2022

PROG

(PARI)f(n) = my(D = Vec(concat(apply(s->Str(s), [1..n])))); eval(concat(vector(#D, k, D[#D-k+1]))); \\ A138793

a(n) = if(n == 1, 1, vecmax(factor(f(n))[, 1])); \\ Daniel Suteu, May 26 2022

STATUS

approved

editing