The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A025487 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A025487

Least integer of each prime signature A124832; also products of primorial numbers A002110.
(history; published version)

#168 by Michael De Vlieger at Thu Nov 30 23:34:02 EST 2023

STATUS

proposed

approved

#167 by Jon E. Schoenfield at Thu Nov 30 23:28:37 EST 2023

STATUS

editing

proposed

#166 by Jon E. Schoenfield at Thu Nov 30 20:01:45 EST 2023

LINKS

Will Nicholes and Franklin T. Adams-Watters, <a href="/A025487/b025487.txt">Table of n, a(n) for n = 1..10001</a> (Will Nicholes supplied the first 291 terms. from Will Nicholes)

STATUS

approved

editing

#165 by Charles R Greathouse IV at Tue Dec 06 14:30:23 EST 2022

STATUS

editing

approved

#164 by Charles R Greathouse IV at Tue Dec 06 14:30:14 EST 2022

PROG

(PARI) upto(Nmax)=vecsort(concat(vector(logint(Nmax, 2), n, select(t->t<=Nmax, if(n>1, [factorback(primes(#p), Vecrev(p)) || p<-partitions(n)], [1, 2]))))) \\ M. F. Hasler, Jul 17 2019

CROSSREFS

Subsequences of this sequence include: A000079, A000142, A000400, A001013, A001813, A002110, A002182, A005179, A006939, A025527, A056836, A061742, A064350, A066120, A087980, A097212, A097213, A111059, A119840, A119845, A126098, A129912, A140999, A166338, A166470, A166472, A166473, A166475, A167448, A168262, A168263, A168264, A179215, A181555, A181804, A181806, A181809, A181818, A181822, A181823, A181824, A181825, A181826, A181827, A182763, A182862, A182863, A212170, A220264, A220423, A250269, A250270, A260633, A266047, A284456, A300357, A304938, A329894, A330687 ; also A037019 and A330681 (when sorted), possibly also A289132.

STATUS

approved

editing

#163 by Charles R Greathouse IV at Wed Aug 10 16:24:40 EDT 2022

STATUS

editing

approved

#162 by Charles R Greathouse IV at Wed Aug 10 16:24:37 EDT 2022

LINKS

Asaf Cohen Antonir and Asaf Shapira, <a href="https://arxiv.org/abs/2207.09410">An Elementary Proof of a Theorem of Hardy and Ramanujan</a> (2022). arXiv:2207.09410 [math.NT]

CROSSREFS

Subsequence of A055932, A191743, and A324583.

Subsequence of A055932, of A191743 and of A324583.

STATUS

approved

editing

#161 by Charles R Greathouse IV at Sat Feb 05 23:09:02 EST 2022

STATUS

editing

approved

#160 by Charles R Greathouse IV at Sat Feb 05 23:08:58 EST 2022

PROG

(PARI) T(n, f=factor(n))=my(k=#f~); f[, 1]=primes(k+1)[2..k+1]~; f[1, 1]=6; factorback(f)

list(u) = my(v = List([1, 2]), i=2, t); while(v[i] != u, if(2*v[i] <= u, listput(v, 2*v[i]); t = T(v[i]); if(t <= u, listput(v, t))); if(i++>#v, break)); Set(v) \\ Charles R Greathouse IV, Feb 05 2022

STATUS

approved

editing

#159 by Charles R Greathouse IV at Sat Feb 05 22:48:25 EST 2022

STATUS

editing

approved