Like old Julius famously said:
"Omnes numeri naturales in partes tres divisi sunt."
Translated into OEIS parlance, this means:
A001477 = A000040 U A002808 U ?
where 'U' denotes the disjoint union.
The problem is that the OEIS is a database for _infinite_ sequences. And so this fundamental relationship could not be expressed in terms of OEIS-numbers.
Only rarely do the editors make an exception and allow finite sequences. Yesterday they were generous, and now the gap has been closed.
But what is '?' anyway?
Peter Luschny
npub1ky…46pll
2025-09-02 11:27:30 UTC
Author Public Key
npub1ky725xgartjzwvtuqrgrpc0z2d54cf88nm3swawurrmpdezaq0lqr46pllSeen on
wss://relay.momostr.pinkPublished at
2025-09-02 11:27:30 UTCEvent JSON
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"content": "Like old Julius famously said: \n\n\"Omnes numeri naturales in partes tres divisi sunt.\"\n\nTranslated into OEIS parlance, this means:\n\nA001477 = A000040 U A002808 U ? \nwhere 'U' denotes the disjoint union.\n\nThe problem is that the OEIS is a database for _infinite_ sequences. And so this fundamental relationship could not be expressed in terms of OEIS-numbers. \n\nOnly rarely do the editors make an exception and allow finite sequences. Yesterday they were generous, and now the gap has been closed.\n\nBut what is '?' anyway?",
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