A049202
Primes p whose order of primeness A049076(p) is >= 6.
Original entry on oeis.org
127, 709, 5381, 15299, 52711, 87803, 167449, 219613, 318211, 506683, 648391, 919913, 1128889, 1254739, 1471343, 1828669, 2269733, 2364361, 3042161, 3338989, 3509299, 4030889, 4535189, 5054303, 5823667, 6478961, 6816631
Offset: 1
Cf.
A049076,
A000040,
A006450,
A038580,
A049090,
A049203,
A057849,
A057850,
A057851,
A057847,
A058332,
A093047.
-
map(ithprime@@4,select(isprime, [$1..137])); # Peter Luschny, Feb 17 2014
-
Nest[ Prime, Range[35], 6] (* Robert G. Wilson v, Mar 15 2004 *)
-
list(lim)=my(v=List(), q, r, s, t, u); forprime(p=2, lim, if(isprime(q++) && isprime(r++) && isprime(s++) && isprime(t++) && isprime(u++), listput(v, p))); Vec(v) \\ Charles R Greathouse IV, Feb 16 2017
Original entry on oeis.org
5381, 2269733, 17624813, 50728129, 77557187, 131807699, 259336153, 368345293, 440817757, 563167303, 751783477, 1107276647, 1170710369, 1367161723, 1760768239, 2062666783, 2323114841, 2458721501, 2621760397, 2860139341
Offset: 1
Cf.
A049076,
A007821,
A049078,
A049079,
A049080,
A049081,
A058322,
A058324,
A058326,
A058327,
A058328,
A093046,
A006450.
Original entry on oeis.org
52711, 37139213, 326851121, 997525853, 1559861749, 2724711961, 5545806481, 8012791231, 9672485827, 12501968177, 16917026909, 25366202179, 26887732891, 31621854169, 41192432219, 48596930311, 55022031709, 58379844161
Offset: 1
Cf.
A049076,
A007821,
A049078,
A049079,
A049080,
A049081,
A058322,
A058324,
A058325,
A058327,
A058328,
A093046,
A006450.
Original entry on oeis.org
648391, 718064159, 7069067389, 22742734291, 36294260117, 64988430769, 136395369829, 200147986693, 243504973489, 318083817907, 435748987787, 664090238153, 705555301183, 835122557939, 1099216100167, 1305164025929
Offset: 1
Cf.
A049076,
A007821,
A049078,
A049079,
A049080,
A049081,
A058322,
A058324,
A058325,
A058326,
A058328,
A093046,
A006450.
-
Nest[ Prime, Select[ Range[30], !PrimeQ[ # ] &], 10] (* Robert G. Wilson v, Mar 15 2004 *)
A057850
Primes p whose order of primeness A078442(p) is at least 8.
Original entry on oeis.org
5381, 52711, 648391, 2269733, 9737333, 17624813, 37139213, 50728129, 77557187, 131807699, 174440041, 259336153, 326851121, 368345293, 440817757, 563167303, 718064159, 751783477, 997525853, 1107276647, 1170710369, 1367161723
Offset: 1
Cf.
A078442,
A000040,
A006450,
A038580,
A049090,
A049203,
A049202,
A057849,
A057851,
A057847,
A058332,
A093047.
-
Nest[ Prime, Range[35], 8] (* Robert G. Wilson v, Mar 15 2004 *)
-
list(lim)=my(v=List(), q, r, s, t, u, vv, w); forprime(p=2, lim, if(isprime(q++) && isprime(r++) && isprime(s++) && isprime(t++) && isprime(u++) && isprime(vv++) && isprime(w++), listput(v, p))); Vec(v) \\ Charles R Greathouse IV, Feb 19 2017
A135044
a(1)=1, then a(c) = p and a(p) = c, where c = T_c(r,k) and p = T_p(r,k), and where T_p contains the primes arranged in rows by the prime index chain and T_c contains the composites arranged in rows by the order of compositeness. See Formula.
Original entry on oeis.org
1, 4, 9, 2, 16, 7, 6, 13, 3, 19, 26, 17, 8, 23, 41, 5, 12, 67, 10, 29, 59, 37, 14, 83, 179, 11, 43, 331, 20, 47, 39, 109, 277, 157, 53, 431, 22, 1063, 31, 191, 15, 2221, 27, 61, 211, 71, 30, 599, 1787, 919, 241, 3001, 35, 73, 8527, 127, 1153, 79, 21, 19577, 44, 89, 283
Offset: 1
From _Andrew Weimholt_, Jan 29 2014: (Start)
More generally, takes the primes organized in an array according to the sieving process described in the Fernandez paper:
Row[1](n) = 2, 7, 13, 19, 23, ...
Row[2](n) = 3, 17, 41, 67, 83, ...
Row[3](n) = 5, 59, 179, ...
Row[4](n) = 11, 277, ...
Lets call this T_p (n, k)
Also take the composites organized in a similar manner, except we use "composite" numbered positions in our sieve:
Row[1](n) = 4, 6, 8, 10, 14, 20, 22, ...
Row[2](n) = 9, 12, 15, 18, 24, ...
Row[3](n) = 16, 21, 25, ...
Lets call this T_c (n, k)
If we now take the natural numbers and swap each number (except for 1) with the number which holds the same spot in the other array, then we get the sequence: 1, 4, 9, 2, 16, 7, 6, 13, with for example a(8) = 13 (13 holds the same position in the 'prime' table as 8 does in the 'composite' table). (End)
Cf.
A000040,
A007097,
A049076,
A049078 -
A049081,
A058322,
A058324 -
A058328,
A093046,
A002808,
A006508,
A059981,
A078442,
A236854.
-
A135044 := proc(n)
if n = 1 then
1;
elif isprime(n) then
idx := -1 ;
for r from 1 do
for c from 1 do
if A236542(r,c) = n then
idx := [r,c] ;
end if;
if A236542(r,c) >= n then
break;
end if;
end do:
if type(idx,list) then
break;
end if;
end do:
A236536(r,c) ;
else
idx := -1 ;
for r from 1 do
for c from 1 do
if A236536(r,c) = n then
idx := [r,c] ;
end if;
if A236536(r,c) >= n then
break;
end if;
end do:
if type(idx,list) then
break;
end if;
end do:
A236542(r,c) ;
end if;
end proc: # R. J. Mathar, Jan 28 2014
-
Composite[n_Integer] := Block[{k = n + PrimePi@n + 1}, While[k != n + PrimePi@k + 1, k++ ]; k]; Compositeness[n_] := Block[{c = 1, k = n}, While[ !(PrimeQ@k || k == 1), k = k - 1 - PrimePi@k; c++ ]; c]; Primeness[n_] := Block[{c = 1, k = n}, While[ PrimeQ@k, k = PrimePi@k; c++ ]; c];
ckj[k_, j_] := Select[ Table[Composite@n, {n, 10000}], Compositeness@# == j &][[k]]; pkj[k_, j_] := Select[ Table[Prime@n, {n, 3000}], Primeness@# == j &][[k]]; f[0]=0; f[1] = 1;
f[n_] := If[ PrimeQ@ n, pn = Primeness@n; ckj[ Position[ Select[ Table[ Prime@ i, {i, 150}], Primeness@ # == pn &], n][[1, 1]], pn], cn = Compositeness@n; pkj[ Position[ Select[ Table[ Composite@ i, {i, 500}], Compositeness@ # == cn &], n][[1, 1]], cn]]; Array[f, 64] (* Robert G. Wilson v *)
Original entry on oeis.org
3657500101, 12055296811267, 156740126985437, 575411103069067, 966399998477597, 1841803943951113, 4176603711876241, 6373890505436101, 7910004791442043, 10613343313176589, 15000987504638299, 23825707567607467, 25462803625208449, 30634679101122821, 41400950264534519, 49969246522326097
Offset: 1
Cf.
A049076,
A006450,
A114537,
A007821,
A049078,
A049079,
A049080,
A049081,
A058322,
A058324,Cf.
A058325,
A058326,
A058327,
A058328,
A093046,
A283459.
Original entry on oeis.org
88362852307, 392654585611999, 5519908106212193, 21034688742654437, 35843152090509943, 69532764058102673, 161191749822468689, 248761474969923757, 310467261969020581, 419776921940182991, 598644471430113247, 962125183414225879, 1029970322316321083, 1244984735583648473, 1695313841631390713
Offset: 1
Cf.
A049076,
A006450,
A114537,
A007821,
A049078,
A049079,
A049080,
A049081,
A058322,
A058324,
A058325,
A058326,
A058327,
A058328,
A093046,
A283458.
Comments