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A078310
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a(n) = n*rad(n) + 1, where rad = A007947 (squarefree kernel).
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21
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2, 5, 10, 9, 26, 37, 50, 17, 28, 101, 122, 73, 170, 197, 226, 33, 290, 109, 362, 201, 442, 485, 530, 145, 126, 677, 82, 393, 842, 901, 962, 65, 1090, 1157, 1226, 217, 1370, 1445, 1522, 401, 1682, 1765, 1850, 969, 676, 2117, 2210, 289, 344, 501, 2602, 1353
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OFFSET
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1,1
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COMMENTS
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Increase each exponent in the prime factorization by one, then add 1 to the new product. - M. F. Hasler, Jan 22 2017
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LINKS
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FORMULA
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MAPLE
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a:= n-> 1+n*mul(i[1], i=ifactors(n)[2]):
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MATHEMATICA
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PROG
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(Haskell)
a078310 n = n * a007947 n + 1
(PARI) rad(n)=my(f=factor(n)[, 1]); prod(i=1, #f, f[i])
(PARI) a(n)={n=factor(n); n[, 2]+=vectorv(matsize(n)[1], i, 1); factorback(n)+1} \\ M. F. Hasler, Jan 22 2017
(PARI) a(n)=prod(k=1, matsize(n=factor(n))[1], n[k, 1]^(n[k, 2]+1))+1 \\ M. F. Hasler, Jan 22 2017
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CROSSREFS
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Smallest, greatest factor: A078311, A078312, number of factors: A078313, A078314, min, max exponent: A078315, A078316, number, sum of divisors: A078317, A078318, sum of prime factors: A078319, A078320, Euler's totient: A078321, squarefree kernel: A078322, arithmetic derivative: A078323.
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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