A355714 - OEIS

A355714

Numbers k > 0 such that A090252(A355176(k)) does not equal prime(k)^2.

1, 2, 16, 26, 32, 35, 40, 59, 60, 69, 92, 105, 110, 112, 113, 137, 167, 169, 178, 185, 186, 188, 207, 210, 260, 261, 274, 287, 289, 342, 344, 346, 356, 357, 359, 361, 362, 363, 391, 412, 417, 434, 457, 477, 478, 479, 480, 481, 492, 547, 563, 598, 663, 666, 671

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OFFSET

1,2

COMMENTS

In contrast to A354169 (a set theoretic analog of A090252) where we observe many as yet unproved regularities, in A090252 the situation appears to be more complicated. This sequence is intended to help spot these irregularities and perhaps lead to further rules, which probably have no analogy in A354169.

In most cases A090252(A355176(n)) equals prime(a(n))*p where p is prime. Surprisingly p is in many cases greater than prime(a(n)).

Is this sequence infinite?

LINKS

Table of n, a(n) for n=1..55.

FORMULA

A090252(A355176(a(n))) <> A000040(a(n))^2.

A000040(a(n)) divides A090252(A355176(a(n))).

A000040(a(n)) divides A090252(2*A355176(a(n))+1).

CROSSREFS

Cf. A000040, A001248, A090252, A354169, A355176.

Sequence in context: A212765 A343839 A019317 * A344989 A276069 A190046

Adjacent sequences: A355711 A355712 A355713 * A355715 A355716 A355717