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 52 results. Next

A329044 a(n) = A064989(A324886(n)).

Original entry on oeis.org

1, 2, 3, 4, 5, 9, 7, 6, 15, 25, 11, 81, 13, 49, 15625, 36, 17, 225, 19, 625, 117649, 121, 23, 135, 60025, 169, 21, 2401, 29, 21875, 31, 10, 1771561, 289, 697540921, 50625, 37, 361, 4826809, 35, 41, 77, 43, 14641, 84035, 529, 47, 375, 161212051, 3603000625, 24137569, 28561, 53, 441, 2474329, 5764801, 47045881, 841, 59, 42875, 61, 961
Offset: 1

Views

Author

Antti Karttunen, Nov 08 2019

Keywords

Crossrefs

Programs

  • 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(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));

Formula

a(n) = A064989(A324886(n)).
a(A000040(n)) = A000040(n).

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).

A329620 Lexicographically earliest infinite sequence such that a(i) = a(j) => f(i) = f(j), where f(n) = [A046523(n), A246277(A324886(n))].

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, 18, 2, 19, 2, 7, 20, 4, 2, 21, 22, 23, 8, 7, 2, 24, 25, 26, 8, 4, 2, 27, 2, 4, 28, 29, 30, 31, 2, 7, 8, 32, 2, 33, 2, 4, 34, 7, 35, 31, 2, 36, 37, 4, 2, 38, 39, 4, 8, 26, 2, 40, 41, 7, 8, 4, 42, 43, 2, 44, 45, 46, 2, 31, 2, 26, 47
Offset: 1

Views

Author

Antti Karttunen, Nov 18 2019

Keywords

Comments

Restricted growth sequence transform of the ordered pair [A046523(n), A246277(A324886(n))].
For all i, j:
A305800(i) = A305800(j) => a(i) = a(j),
a(i) = a(j) => A101296(i) = A101296(j),
a(i) = a(j) => A329345(i) = A329345(j),
a(i) = a(j) => A329618(i) = A329618(j),
a(i) = a(j) => A329619(i) = A329619(j).

Crossrefs

Programs

  • PARI
    up_to = 8192;
    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; };
    A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); }; \\ From A046523
    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));
    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);
    Aux329620(n) = [A046523(n), A246277(A324886(n))];
    v329620 = rgs_transform(vector(up_to, n, Aux329620(n)));
    A329620(n) = v329620[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.

A346098 a(n) = A064989(A346096(n)) = A064989(A319626(A324886(n))).

Original entry on oeis.org

1, 2, 3, 4, 5, 9, 7, 3, 5, 25, 11, 81, 13, 49, 15625, 9, 17, 25, 19, 625, 117649, 121, 23, 45, 2401, 169, 21, 2401, 29, 4375, 31, 10, 1771561, 289, 14235529, 625, 37, 361, 4826809, 7, 41, 11, 43, 14641, 16807, 529, 47, 125, 2093663, 5764801, 24137569, 28561, 53, 441, 20449, 5764801, 47045881, 841, 59, 343, 61, 961, 1331, 100, 396067447082177
Offset: 1

Views

Author

Antti Karttunen, Jul 07 2021

Keywords

Crossrefs

Cf. A064989, A319626, A324886, A346095, A346096, A346097, A346099 [= gcd(n, a(n))].

Programs

Formula

A329047 a(n) = A003415(A324886(n)).

Original entry on oeis.org

1, 1, 1, 6, 1, 10, 1, 8, 12, 14, 1, 500, 1, 22, 100842, 240, 1, 840, 1, 1372, 966306, 26, 1, 650, 465850, 34, 16, 5324, 1, 148862, 1, 10, 2227758, 38, 31919986098, 2058000, 1, 46, 8519142, 18, 1, 24, 1, 8788, 673486, 58, 1, 1078, 551741398, 668409965300, 14856594, 19652, 1, 1760, 3510806, 155897368, 38618058, 62, 1, 320166, 1, 74, 1472328, 420
Offset: 1

Views

Author

Antti Karttunen, Nov 08 2019

Keywords

Crossrefs

Programs

Formula

a(n) = A327860(A108951(n)).

A324896 Largest proper divisor of A324886(n).

Original entry on oeis.org

1, 1, 1, 3, 1, 5, 1, 5, 7, 7, 1, 125, 1, 11, 16807, 75, 1, 245, 1, 343, 161051, 13, 1, 175, 102487, 17, 11, 1331, 1, 26411, 1, 7, 371293, 19, 3293331899, 300125, 1, 23, 1419857, 11, 1, 13, 1, 2197, 161051, 29, 1, 343, 82055753, 73525096183, 2476099, 4913, 1, 605, 634933, 19487171, 6436343, 31, 1, 65219, 1, 37, 265837, 147
Offset: 1

Views

Author

Antti Karttunen, Mar 30 2019

Keywords

Crossrefs

Programs

Formula

a(n) = A032742(A324886(n)) = A324895(A108951(n)).

A329046 a(n) = A000005(A324886(n)).

Original entry on oeis.org

2, 2, 2, 3, 2, 3, 2, 4, 4, 3, 2, 5, 2, 3, 7, 9, 2, 9, 2, 5, 7, 3, 2, 8, 15, 3, 4, 5, 2, 12, 2, 4, 7, 3, 27, 25, 2, 3, 7, 4, 2, 4, 2, 5, 12, 3, 2, 8, 28, 45, 7, 5, 2, 9, 15, 9, 7, 3, 2, 16, 2, 3, 16, 9, 28, 13, 2, 5, 7, 36, 2, 24, 2, 3, 72, 5, 51, 13, 2, 9, 28, 3, 2, 9, 24, 3, 7, 9, 2, 33, 91, 5, 7, 3, 16, 21, 2, 117, 33, 28, 2, 13, 2, 9, 40
Offset: 1

Views

Author

Antti Karttunen, Nov 08 2019

Keywords

Crossrefs

Programs

Formula

a(n) = A324655(A108951(n)).

A329621 a(n) = gcd(A056239(n), A324888(n)) = gcd(A001222(A108951(n)), A001222(A324886(n))).

Original entry on oeis.org

1, 1, 1, 2, 1, 1, 1, 1, 2, 2, 1, 4, 1, 1, 1, 4, 1, 1, 1, 1, 6, 2, 1, 1, 6, 1, 2, 2, 1, 6, 1, 1, 1, 2, 1, 2, 1, 1, 2, 2, 1, 1, 1, 1, 1, 2, 1, 2, 8, 1, 3, 4, 1, 1, 2, 1, 2, 1, 1, 1, 1, 2, 2, 2, 1, 4, 1, 1, 1, 2, 1, 1, 1, 1, 2, 2, 9, 3, 1, 1, 8, 2, 1, 4, 2, 1, 6, 8, 1, 4, 2, 1, 1, 2, 1, 1, 1, 1, 3, 8, 1, 2, 1, 1, 1
Offset: 1

Views

Author

Antti Karttunen, Nov 18 2019

Keywords

Crossrefs

Programs

  • Mathematica
    With[{b = MixedRadix[Reverse@ Prime@ Range@ 500]}, Array[GCD @@ PrimeOmega@ {#, Function[k, Times @@ Power @@@ # &@ Transpose@ {Prime@ Range@ Length@ k, Reverse@ k}]@ IntegerDigits[#, b]} &@ Apply[Times, Map[#1^#2 & @@ # &, FactorInteger[#] /. {p_, e_} /; e > 0 :> {Times @@ Prime@ Range@ PrimePi@ p, e}]] &, 105]] (* Michael De Vlieger, Nov 18 2019 *)
  • 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(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
    A329621(n) = { my(u=A108951(n)); gcd(bigomega(u), bigomega(A276086(u))); };

Formula

a(n) = gcd(A056239(n), A324888(n)) = gcd(A001222(A108951(n)), A001222(A324886(n))).
Showing 1-10 of 52 results. Next