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.

Showing 1-10 of 11 results. Next

A329045 Lexicographically earliest infinite sequence such that a(i) = a(j) => A046523(A329044(i)) = A046523(A329044(j)) for all i, j.

Original entry on oeis.org

1, 2, 2, 3, 2, 3, 2, 4, 4, 3, 2, 5, 2, 3, 6, 7, 2, 7, 2, 5, 6, 3, 2, 8, 9, 3, 4, 5, 2, 10, 2, 4, 6, 3, 11, 12, 2, 3, 6, 4, 2, 4, 2, 5, 10, 3, 2, 8, 13, 14, 6, 5, 2, 7, 9, 15, 6, 3, 2, 16, 2, 3, 16, 7, 17, 18, 2, 5, 6, 19, 2, 20, 2, 3, 21, 5, 22, 18, 2, 7, 13, 3, 2, 7, 23, 3, 6, 15, 2, 24, 25, 5, 6, 3, 26, 27, 2, 28, 24, 13, 2, 18, 2, 15, 29
Offset: 1

Views

Author

Antti Karttunen, Nov 08 2019

Keywords

Comments

Restricted growth sequence transform of function f(n) = A046523(A329044(n)).
For all i, j:
A305800(i) = A305800(j) => a(i) = a(j),
a(i) = a(j) => A324888(i) = A324888(j),
a(i) = a(j) => A329046(i) = A329046(j).

Crossrefs

Programs

  • PARI
    up_to = 65537;
    rgs_transform(invec) = { my(om = Map(), outvec = vector(length(invec)), u=1); for(i=1, length(invec), if(mapisdefined(om,invec[i]), my(pp = mapget(om, invec[i])); outvec[i] = outvec[pp] , mapput(om,invec[i],i); outvec[i] = u; u++ )); outvec; };
    A034386(n) = prod(i=1, primepi(n), prime(i));
    A108951(n) = { my(f=factor(n)); prod(i=1, #f~, A034386(f[i, 1])^f[i, 2]) };  \\ From A108951
    A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
    A324886(n) = A276086(A108951(n));
    A064989(n) = {my(f); f = factor(n); if((n>1 && f[1,1]==2), f[1,2] = 0); for (i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f)};
    A329044(n) = A064989(A324886(n));
    A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); }; \\ From A046523
    v329045 = rgs_transform(vector(up_to, n, A046523(A329044(n))));
    A329045(n) = v329045[n];

A329345 Lexicographically earliest infinite sequence such that a(i) = a(j) => A246277(A329044(i)) = A246277(A329044(j)) for all i, j.

Original entry on oeis.org

1, 2, 2, 3, 2, 3, 2, 4, 4, 3, 2, 5, 2, 3, 6, 7, 2, 7, 2, 5, 6, 3, 2, 8, 9, 3, 10, 5, 2, 11, 2, 10, 6, 3, 12, 13, 2, 3, 6, 4, 2, 4, 2, 5, 14, 3, 2, 15, 16, 17, 6, 5, 2, 18, 19, 20, 6, 3, 2, 21, 2, 3, 21, 18, 22, 23, 2, 5, 6, 24, 2, 25, 2, 3, 26, 5, 27, 23, 2, 7, 28, 3, 2, 7, 29, 3, 6, 20, 2, 30, 31, 5, 6, 3, 32, 33, 2, 34, 35, 16, 2, 23, 2, 20, 36
Offset: 1

Views

Author

Antti Karttunen, Nov 11 2019

Keywords

Comments

Restricted growth sequence transform of function f(n) = A246277(A329044(n)).
For all i, j:
A305800(i) = A305800(j) => a(i) = a(j),
a(i) = a(j) => A329045(i) = A329045(j),
a(i) = a(j) => A329343(i) = A329343(j),
a(i) = a(j) => A329348(i) = A329348(j),
a(i) = a(j) => A329349(i) = A329349(j).

Crossrefs

Programs

  • PARI
    up_to = 1024;
    rgs_transform(invec) = { my(om = Map(), outvec = vector(length(invec)), u=1); for(i=1, length(invec), if(mapisdefined(om,invec[i]), my(pp = mapget(om, invec[i])); outvec[i] = outvec[pp] , mapput(om,invec[i],i); outvec[i] = u; u++ )); outvec; };
    A034386(n) = prod(i=1, primepi(n), prime(i));
    A108951(n) = { my(f=factor(n)); prod(i=1, #f~, A034386(f[i, 1])^f[i, 2]) };  \\ From A108951
    A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
    A324886(n) = A276086(A108951(n));
    A064989(n) = {my(f); f = factor(n); if((n>1 && f[1,1]==2), f[1,2] = 0); for (i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f)};
    A329044(n) = A064989(A324886(n));
    A246277(n) = if(1==n, 0, my(f = factor(n), k = primepi(f[1,1])-1); for (i=1, #f~, f[i,1] = prime(primepi(f[i,1])-k)); factorback(f)/2);
    v329345 = rgs_transform(vector(up_to, n, A246277(A329044(n))));
    A329345(n) = v329345[n];

A345941 a(n) = gcd(n, A329044(n)).

Original entry on oeis.org

1, 2, 3, 4, 5, 3, 7, 2, 3, 5, 11, 3, 13, 7, 5, 4, 17, 9, 19, 5, 7, 11, 23, 3, 25, 13, 3, 7, 29, 5, 31, 2, 11, 17, 7, 9, 37, 19, 13, 5, 41, 7, 43, 11, 5, 23, 47, 3, 7, 25, 17, 13, 53, 9, 11, 7, 19, 29, 59, 5, 61, 31, 7, 4, 13, 11, 67, 17, 23, 7, 71, 9, 73, 37, 25, 19, 11, 13, 79, 5, 3, 41, 83, 7, 17, 43, 29, 11, 89
Offset: 1

Views

Author

Antti Karttunen, Jul 03 2021

Keywords

Comments

Only powers of primes (A000961) occur as terms. A346087 gives the exponents. - Antti Karttunen, Jul 07 2021

Crossrefs

Programs

Formula

a(n) = gcd(n, A329044(n)).
a(n) = n / A345942(n).
a(n) = A329044(n) / A345943(n).
a(p) = p for all primes p.
From Antti Karttunen, Jul 07 2021: (Start)
a(n) = A006530(n)^A346087(n) = A006530(n)^min(A071178(n), A329348(n)).
a(n) = gcd(n, A346097(n)).
A006530(a(n)) = A020639(A329044(n)) = A006530(n).
(End)

A345942 a(n) = n / gcd(n, A329044(n)).

Original entry on oeis.org

1, 1, 1, 1, 1, 2, 1, 4, 3, 2, 1, 4, 1, 2, 3, 4, 1, 2, 1, 4, 3, 2, 1, 8, 1, 2, 9, 4, 1, 6, 1, 16, 3, 2, 5, 4, 1, 2, 3, 8, 1, 6, 1, 4, 9, 2, 1, 16, 7, 2, 3, 4, 1, 6, 5, 8, 3, 2, 1, 12, 1, 2, 9, 16, 5, 6, 1, 4, 3, 10, 1, 8, 1, 2, 3, 4, 7, 6, 1, 16, 27, 2, 1, 12, 5, 2, 3, 8, 1, 18, 7, 4, 3, 2, 5, 32, 1, 2, 9, 20, 1, 6
Offset: 1

Views

Author

Antti Karttunen, Jul 03 2021

Keywords

Crossrefs

Programs

Formula

a(n) = n / A345941(n).

A345943 a(n) = A329044(n) / gcd(n, A329044(n)).

Original entry on oeis.org

1, 1, 1, 1, 1, 3, 1, 3, 5, 5, 1, 27, 1, 7, 3125, 9, 1, 25, 1, 125, 16807, 11, 1, 45, 2401, 13, 7, 343, 1, 4375, 1, 5, 161051, 17, 99648703, 5625, 1, 19, 371293, 7, 1, 11, 1, 1331, 16807, 23, 1, 125, 23030293, 144120025, 1419857, 2197, 1, 49, 224939, 823543, 2476099, 29, 1, 8575, 1, 31, 65219, 25, 396067447082177, 285311670611
Offset: 1

Views

Author

Antti Karttunen, Jul 04 2021

Keywords

Crossrefs

Programs

Formula

a(n) = A329044(n) / A345941(n) = A329044(n) / gcd(n, A329044(n)).

A351949 Lexicographically earliest infinite sequence such that a(i) = a(j) => A246277(A329044(i)) = A246277(A329044(j)) and A003557(i) = A003557(j), for all i, j >= 1.

Original entry on oeis.org

1, 2, 2, 3, 2, 4, 2, 5, 6, 4, 2, 7, 2, 4, 8, 9, 2, 10, 2, 7, 8, 4, 2, 11, 12, 4, 13, 7, 2, 14, 2, 15, 8, 4, 16, 17, 2, 4, 8, 5, 2, 18, 2, 7, 19, 4, 2, 20, 21, 22, 8, 7, 2, 23, 24, 25, 8, 4, 2, 26, 2, 4, 27, 28, 29, 30, 2, 7, 8, 31, 2, 32, 2, 4, 33, 7, 34, 30, 2, 9, 35, 4, 2, 36, 37, 4, 8, 25, 2, 38, 39, 7, 8, 4, 40
Offset: 1

Views

Author

Antti Karttunen, Apr 05 2022

Keywords

Comments

Restricted growth sequence transform of the ordered pair [A003557(n), A329345(n)].

Crossrefs

Programs

  • PARI
    up_to = 65537;
    rgs_transform(invec) = { my(om = Map(), outvec = vector(length(invec)), u=1); for(i=1, length(invec), if(mapisdefined(om,invec[i]), my(pp = mapget(om, invec[i])); outvec[i] = outvec[pp] , mapput(om,invec[i],i); outvec[i] = u; u++ )); outvec; };
    A003557(n) = (n/factorback(factorint(n)[, 1]));
    A034386(n) = prod(i=1, primepi(n), prime(i));
    A108951(n) = { my(f=factor(n)); prod(i=1, #f~, A034386(f[i, 1])^f[i, 2]) };
    A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
    A324886(n) = A276086(A108951(n));
    A064989(n) = {my(f); f = factor(n); if((n>1 && f[1,1]==2), f[1,2] = 0); for (i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f)};
    A329044(n) = A064989(A324886(n));
    A246277(n) = if(1==n, 0, my(f = factor(n), k = primepi(f[1,1])-1); for (i=1, #f~, f[i,1] = prime(primepi(f[i,1])-k)); factorback(f)/2);
    v351949 = rgs_transform(vector(up_to, n, [A003557(n), A246277(A329044(n))]));
    A351949(n) = v351949[n];

A324886 a(n) = A276086(A108951(n)).

Original entry on oeis.org

2, 3, 5, 9, 7, 25, 11, 15, 35, 49, 13, 625, 17, 121, 117649, 225, 19, 1225, 23, 2401, 1771561, 169, 29, 875, 717409, 289, 55, 14641, 31, 184877, 37, 21, 4826809, 361, 36226650889, 1500625, 41, 529, 24137569, 77, 43, 143, 47, 28561, 1127357, 841, 53, 1715, 902613283, 514675673281, 47045881, 83521, 59, 3025, 8254129, 214358881, 148035889, 961, 61
Offset: 1

Views

Author

Antti Karttunen, Mar 30 2019

Keywords

Crossrefs

Programs

  • Mathematica
    With[{b = MixedRadix[Reverse@ Prime@ Range@ 120]}, Array[Function[k, Times @@ Power @@@ # &@ Transpose@ {Prime@ Range@ Length@ k, Reverse@ k}]@ IntegerDigits[Apply[Times, Map[#1^#2 & @@ # &, FactorInteger[#] /. {p_, e_} /; e > 0 :> {Times @@ Prime@ Range@ PrimePi@ p, e}]], b] &, 58]] (* Michael De Vlieger, Nov 18 2019 *)
    A276086[n0_] := Module[{m = 1, i = 1, n = n0, p}, While[n > 0, p = Prime[i]; m *= p^Mod[n, p]; n = Quotient[n, p]; i++]; m];
    (* b is A108951 *)
    b[n_] := b[n] = Module[{pe = FactorInteger[n], p, e}, If[Length[pe] > 1, Times @@ b /@ Power @@@ pe, {{p, e}} = pe; Times @@ (Prime[Range[ PrimePi[p]]]^e)]]; b[1] = 1;
    a[n_] := A276086[b[n]];
    Array[a, 100] (* Jean-François Alcover, Dec 01 2021, after _Antti Karttunen in A296086 *)
  • PARI
    A034386(n) = prod(i=1, primepi(n), prime(i));
    A108951(n) = { my(f=factor(n)); prod(i=1, #f~, A034386(f[i, 1])^f[i, 2]) };  \\ From A108951
    A276086(n) = { my(i=0,m=1,pr=1,nextpr); while((n>0),i=i+1; nextpr = prime(i)*pr; if((n%nextpr),m*=(prime(i)^((n%nextpr)/pr));n-=(n%nextpr));pr=nextpr); m; };
    A324886(n) = A276086(A108951(n));

Formula

a(n) = A276086(A108951(n)).
a(n) = A117366(n) * A324896(n).
A001222(a(n)) = A324888(n).
A020639(a(n)) = A117366(n).
A032742(a(n)) = A324896(n).
a(A000040(n)) = A000040(1+n).
From Antti Karttunen, Jul 09 2021: (Start)
For n > 1, a(n) = A003961(A329044(n)).
a(n) = A346091(n) * A344592(n).
a(n) = A346106(n) / A346107(n).
A003415(a(n)) = A329047(n).
A003557(a(n)) = A344592(n).
A342001(a(n)) = A342920(n) = A329047(n) / A344592(n).
(End)

A346096 Numerator of the primorial deflation of A276086(A108951(n)): a(n) = A319626(A324886(n)).

Original entry on oeis.org

2, 3, 5, 9, 7, 25, 11, 5, 7, 49, 13, 625, 17, 121, 117649, 25, 19, 49, 23, 2401, 1771561, 169, 29, 175, 14641, 289, 55, 14641, 31, 26411, 37, 21, 4826809, 361, 299393809, 2401, 41, 529, 24137569, 11, 43, 13, 47, 28561, 161051, 841, 53, 343, 6311981, 214358881, 47045881, 83521, 59, 3025, 48841, 214358881, 148035889, 961
Offset: 1

Views

Author

Antti Karttunen, Jul 07 2021

Keywords

Comments

Numerator of ratio A324886(n) / A329044(n).

Crossrefs

Programs

Formula

a(n) = A319626(A324886(n)).
a(n) = A324886(n) / A346095(n) = A324886(n) / gcd(A324886(n), A329044(n)).
For n >= 1, A108951(A346096(n)) / A108951(A346097(n)) = A324886(n).
For n > 1, a(n) = A003961(A346098(n)).

A346097 Denominator of the primorial deflation of A276086(A108951(n)): a(n) = A319627(A324886(n)).

Original entry on oeis.org

1, 2, 3, 4, 5, 9, 7, 2, 3, 25, 11, 81, 13, 49, 15625, 4, 17, 9, 19, 625, 117649, 121, 23, 27, 1225, 169, 21, 2401, 29, 3125, 31, 10, 1771561, 289, 5764801, 81, 37, 361, 4826809, 5, 41, 7, 43, 14641, 12005, 529, 47, 75, 1127357, 1500625, 24137569, 28561, 53, 441, 14641, 5764801, 47045881, 841, 59, 125, 61, 961, 343, 100, 302875106592253
Offset: 1

Views

Author

Antti Karttunen, Jul 07 2021

Keywords

Comments

Denominator of ratio A324886(n) / A329044(n).

Crossrefs

Cf. A346096 (numerators).
Cf. also A337377.

Programs

Formula

a(n) = A319627(A324886(n)).
a(n) = A329044(n) / A346095(n) = A329044(n) / gcd(A324886(n), A329044(n)).
A020639(a(n)) = A006530(n).
A108951(a(n)) = A346107(n).
A346105(a(n)) = A346109(n).

A346095 a(n) = gcd(A324886(n), A064989(A324886(n))).

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 3, 5, 1, 1, 1, 1, 1, 1, 9, 1, 25, 1, 1, 1, 1, 1, 5, 49, 1, 1, 1, 1, 7, 1, 1, 1, 1, 121, 625, 1, 1, 1, 7, 1, 11, 1, 1, 7, 1, 1, 5, 143, 2401, 1, 1, 1, 1, 169, 1, 1, 1, 1, 343, 1, 1, 1331, 1, 17, 1, 1, 1, 1, 161051, 1, 175, 1, 1, 41503, 1, 169, 1, 1, 49, 35, 1, 1, 121, 19, 1, 1, 1, 1, 49, 24137569
Offset: 1

Views

Author

Antti Karttunen, Jul 07 2021

Keywords

Crossrefs

Programs

  • PARI
    A330749(n) = {my(f); f = factor(n); if((n>1 && f[1, 1]==2), f[1, 2] = 0); for (i=1, #f~, f[i, 1] = precprime(f[i, 1]-1)); gcd(n, factorback(f)); };
    A346095(n) = A330749(A324886(n)); \\ Rest of program given in A324886.

Formula

a(n) = A330749(A324886(n)) = gcd(A324886(n), A329044(n)) = gcd(A324886(n), A064989(A324886(n))).
a(n) = A324886(n) / A346096(n).
a(n) = A329044(n) / A346097(n).
a(n) mod A006530(n) > 0, for all n > 1.
Showing 1-10 of 11 results. Next