A245486 -id:A245486 - cp's OEIS frontend

A332951 Numbers m such that A245486(k) = m for some k.

2, 6, 10, 14, 15, 21, 22, 26, 33, 34, 35, 38, 39, 51, 55, 57, 62, 65, 69, 77, 82, 85, 86, 87, 91, 93, 95, 111, 115, 119, 123, 129, 133, 141, 143, 145, 146, 155, 159, 161, 177, 178, 183, 185, 187, 201, 203, 205, 209, 213, 215, 217, 218, 219, 221, 226, 235, 237, 247

Offset: 1

Jinyuan Wang, Mar 04 2020

nonn

Also the union of 2 and squarefree semiprimes which never occur in A332952. See A245486 for more information.

			218 = 2*109 is in the sequence because A245486(262144) = 218.

Romanian Master in Mathematics Contest, Bucharest, 2020, Problem 6

Cf. A000040, A006530, A006881, A014664, A245486, A332952.

A332952 Squarefree semiprimes which never occur in A245486.

Original entry on oeis.org

46, 58, 74, 94, 106, 118, 122, 134, 142, 158, 166, 194, 202, 206, 214, 262, 267, 274, 278, 298, 309, 314, 326, 334, 339, 346, 358, 362

Offset: 1

Jinyuan Wang, Mar 04 2020

Also squarefree semiprimes which never occur in A332951.
This sequence is infinite. It appears that all terms can be divisible by 2 or 3.
If A014664(i) = A014664(j) for some 1 < i < j, then 2*prime(i) is a term. See A245486 for more information.

			a(2) = 58 because when 2^m - 1 or 2^m + 1 is divisible by 29, it's also divisible by 113. Therefore, there's no integer k such that A245486(k) = A006530(k) * A006530(k+1) = 58.

Romanian Master in Mathematics Contest, Bucharest, 2020, Problem 6

Cf. A000040, A006530, A006881, A014664, A245486, A332951.

cp's OEIS Frontend

A332951 Numbers m such that A245486(k) = m for some k.

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