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A283484 Odd bisection of A283983; square root of the largest square dividing A277324. 5
1, 1, 3, 1, 3, 3, 15, 1, 3, 15, 45, 15, 15, 15, 105, 1, 3, 105, 225, 525, 1575, 1125, 1575, 105, 105, 525, 1575, 525, 105, 105, 1155, 1, 3, 1155, 1575, 3675, 7875, 275625, 55125, 5775, 17325, 275625, 4134375, 55125, 55125, 275625, 121275, 1155, 1155, 40425, 385875, 202125, 606375, 1929375, 606375, 5775, 8085, 40425, 121275, 40425, 1155, 1155, 15015, 1, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Antti Karttunen, Table of n, a(n) for n = 0..2048

FORMULA

a(n) = A283983((2*n)+1).

a(n) = A000188(A277324(n)).

A001222(a(n)) = A284265(n).

MATHEMATICA

A003961[p_?PrimeQ] := A003961[p] = Prime[ PrimePi[p] + 1]; A003961[1] = 1; A003961[n_] := A003961[n] = Times @@ ( A003961[First[#]] ^ Last[#] & ) /@ FactorInteger[n]  (* after Jean-Fran├žois Alcover, Dec 01 2011 *); A260443[n_]:= If[n<2, n + 1, If[EvenQ[n], A003961[A260443[n/2]], A260443[(n - 1)/2] * A260443[(n + 1)/2]]]; A275812[n_]:= PrimeOmega[n] - If[n<2, 0, Count[Transpose[FactorInteger[n]][[2]], 1]]; A277324[n_]:=A260443[2n + 1];  A000188[n_]:=  Sum[Boole[Mod[i^2, n] == 0], {i, n}]; Table[A000188[A277324[n]], {n, 0, 50}] (* Indranil Ghosh, Mar 28 2017 *)

PROG

(PARI)

A003961(n) = my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); \\ From Michel Marcus

A260443(n) = if(n<2, n+1, if(n%2, A260443(n\2)*A260443(n\2+1),  A003961(A260443(n\2)))); \\ Cf. Charles R Greathouse IV's code for "ps" in A186891 and A277013.

A277324(n) = A260443((2*n)+1);

A000188(n) = core(n, 1)[2]; \\ This function from Michel Marcus, Feb 27 2013

A283484(n) = A000188(A277324(n));

(Scheme)

(define (A283484 n) (A000188 (A277324 n)))

(define (A283484 n) (A283983 (+ n n 1)))

CROSSREFS

Cf. A000188, A001222, A277324, A283983, A284265.

Sequence in context: A238313 A163270 A098743 * A130560 A088105 A030708

Adjacent sequences:  A283481 A283482 A283483 * A283485 A283486 A283487

KEYWORD

nonn

AUTHOR

Antti Karttunen, Mar 25 2017

STATUS

approved

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Last modified October 13 18:14 EDT 2019. Contains 327981 sequences. (Running on oeis4.)