The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A260713 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
Showing entries 1-10 | older changes

A260713

Number of iterations of A234742 needed when starting from A236844(n) before a fixed point is reached.
(history; published version)

#12 by N. J. A. Sloane at Thu Aug 06 07:41:39 EDT 2015

STATUS

editing

approved

#11 by N. J. A. Sloane at Thu Aug 06 07:41:08 EDT 2015

NAME

Number of iterations of A234742 needed when started starting from A236844(n), before a fixed point is reached.

STATUS

proposed

editing

Discussion

Thu Aug 06

07:41

N. J. A. Sloane: minor improvements to defn.

#10 by Jon E. Schoenfield at Thu Aug 06 00:41:49 EDT 2015

STATUS

editing

proposed

#9 by Jon E. Schoenfield at Thu Aug 06 00:41:47 EDT 2015

COMMENTS

It is not known whether the sequence is well-defined for all values. For example, has does a(190) have a finite value? Cf. sequence A260735, starting iteration from 455 = A236844(190).

STATUS

proposed

editing

#8 by Antti Karttunen at Wed Aug 05 04:58:21 EDT 2015

STATUS

editing

proposed

#7 by Antti Karttunen at Tue Aug 04 18:34:39 EDT 2015

PROG

A260712(n) = {my(prev=-1, i=-1); until((n==prev), prev = n; n = A234742(n); i++); return(i); } \\ The name was n_iterations_of_A234742_to_fixed_point;

#6 by Antti Karttunen at Tue Aug 04 15:52:47 EDT 2015

COMMENTS

It is not known whether the sequence is well-defined for all values. For example, has a(190) a finite value? Cf. sequence A260735, starting iteration from 455 = A236844(190) = 455.

#5 by Antti Karttunen at Tue Aug 04 15:51:48 EDT 2015

COMMENTS

It is not known whether the sequence is well-defined for all values. For example, has a(190) a finite value? Cf. sequence A260735, starting from A236844(190) = 455.

CROSSREFS

Cf. A234742, A236844, A260712, A260735.

#4 by Antti Karttunen at Tue Aug 04 15:42:53 EDT 2015

CROSSREFS

Subsequence: A260716.

#3 by Antti Karttunen at Tue Aug 04 15:31:07 EDT 2015

LINKS

Antti Karttunen, <a href="/A260713/b260713.txt">Table of n, a(n) for n = 1..189</a>

PROG

(PARI)

allocatemem((2^29));

v236844 = [5, 10, 15, 17, 20, 23, 29, 30, 34, 35, 40, 43, 45, 46, 51, 53, 58, 60, 65, 68, 69, 70, 71, 79, 80, 83, 85, 86, 89, 90, 92, 95, 101, 102, 105, 106, 107, 113, 116, 119, 120, 125, 127, 129, 130, 135, 136, 138, 139, 140, 142, 149, 151, 153, 155, 158, 159, 160, 161, 163, 166, 170, 172, 173, 178, 179, 180, 181, 184, 187, 190, 195, 197, 199, 202, 204, 205, 207, 210, 212, 214, 215, 221, 223, 226, 227, 232, 233, 235, 237, 238, 240, 245, 249, 250, 251, 254, 255, 257, 258, 260, 263, 265, 267, 269, 270, 271, 272, 276, 277, 278, 280, 281, 284, 289, 293, 295, 298, 302, 303, 305, 306, 307, 310, 311, 315, 316, 317, 318, 320, 321, 322, 323, 326, 331, 332, 335, 337, 339, 340, 344, 346, 347, 349, 353, 356, 358, 359, 360, 362, 365, 367, 368, 371, 373, 374, 377, 380, 381, 383, 387, 389, 390, 394, 398, 401, 404, 405, 408, 409, 410, 414, 417, 420, 421, 424, 428, 430, 431, 437, 439, 442, 443, 446, 447, 449, 452, 453, 454];

A236844(n) = v236844[n];

A234742(n) = factorback(subst(lift(factor(Mod(1, 2)*Pol(binary(n)))), x, 2)); \\ After M. F. Hasler's Feb 18 2014 code.

A260712(n) = {my(prev=-1, i=-1); until((n==prev), prev = n; n = A234742(n); i++); return(i); } \\ The name was n_iterations_of_A234742_to_fixed_point

A260713(n) = A260712(A236844(n));

for(n=1, 189, write("b260713.txt", n, " ", A260713(n)));