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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.

A347120 Square root of the largest square dividing A005940(1+(3*A156552(n))): a(n) = A000188(A332449(n)).

Original entry on oeis.org

1, 2, 3, 1, 5, 4, 7, 1, 1, 6, 11, 1, 13, 10, 9, 3, 17, 2, 19, 5, 15, 14, 23, 1, 1, 22, 1, 7, 29, 8, 31, 3, 21, 26, 25, 1, 37, 34, 33, 5, 41, 12, 43, 11, 1, 38, 47, 3, 1, 2, 39, 13, 53, 2, 35, 7, 51, 46, 59, 1, 61, 58, 7, 9, 55, 20, 67, 17, 57, 18, 71, 1, 73, 62, 3, 19, 49, 28, 79, 15, 5, 74, 83, 11, 65, 82, 69, 11, 89
Offset: 1

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Author

Antti Karttunen, Aug 22 2021

Keywords

Crossrefs

Programs

  • PARI
    A000188(n) = core(n, 1)[2]; \\ This function from A000188
    A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); (t); };
    A156552(n) = { my(f = factor(n), p, p2 = 1, res = 0); for(i = 1, #f~, p = 1 << (primepi(f[i, 1]) - 1); res += (p * p2 * (2^(f[i, 2]) - 1)); p2 <<= f[i, 2]); res };
    A332449(n) = A005940(1+(3*A156552(n)));
    A347120(n) = A000188(A332449(n));

Formula

a(n) = A000188(A332449(n)).
a(n) = A000196(A332449(n)/A347119(n)).
a(p) = p for all primes p.